DTC DETECTION LOGIC AND CONDITIONS


BHE010200102T03

P0030 Front HO2S heater control circuit problem

• The PCM monitors the front HO2S impedance when under the front HO2S heater control for 200 s. If the impedance is more than 44 ohms, the PCM determines that there is a front HO2S heater control circuit problem.

P0031 Front HO2S heater control circuit low

• The PCM monitors the front HO2S heater control voltage when the PCM turns the front HO2S heater off. If the control voltage exceeds 25 % of the battery voltage, the PCM determines that the front HO2S heater control circuit voltage is low.

P0032 Front HO2S heater control circuit high

• The PCM monitors the front HO2S heater control voltage when the PCM turns the front HO2S heater on. If the control voltage is less than 25 % of the battery voltage, the PCM determines that the front HO2S heater control circuit voltage is high.

P0037 Rear HO2S heater control circuit low

• The PCM monitors the rear HO2S heater control voltage when the PCM turns the rear HO2S heater off. If the control voltage exceeds 57 % of the battery voltage, the PCM determines that the rear HO2S heater control circuit voltage is low.

P0038 Rear HO2S heater control circuit high

• The PCM monitors the rear HO2S heater control voltage when the PCM turns the rear HO2S heater on. If the control voltage is less than 57 % of the battery voltage, the PCM determines that the rear HO2S heater control circuit voltage is high.

P0076 VDI solenoid valve control circuit low

• The PCM monitors the VDI solenoid valve control voltage when the PCM turns the VDI solenoid valve off. If the control voltage is low, the PCM determines that the VDI solenoid valve control circuit voltage is low.

P0077 VDI solenoid valve control circuit high

• The PCM monitors the VDI solenoid valve control voltage when the PCM turns the VDI solenoid valve on. If the control voltage is high, the PCM determines that the VDI solenoid valve control circuit voltage is high.

P0101 MAF sensor circuit range/performance problem

• The PCM compares the actual MAF amount with the expected MAF amount when the engine is running.

– If the throttle opening angle is more than 50 % and the MAF amount is less than 5 g/s {0.66 lb/min}, the PCM determines that there is a MAF sensor circuit range/performance problem.
– If the ECT is more than 70 °C {158 °F}, the engine speed is less than 2,000 rpm and the MAF amount is more than 130 g/s {17.20 lb/min} (MT) 110 g/s {14.55 lb/min} (AT), the PCM determines that there is a MAF sensor circuit range/performance problem.

P0102 MAF sensor circuit low input

• The PCM monitors the input voltage from the MAF sensor when the engine is running. If the input voltage is less than 0.5 V, the PCM determines that the MAF sensor circuit input voltage is low.

P0103 MAF sensor circuit high input

• The PCM monitors the input voltage from the MAF sensor when the engine is running. If the input voltage is more than 5.0 V, the PCM determines that the MAF sensor circuit input voltage is high.

P0107 BARO sensor circuit low input

• The PCM monitors the input voltage from the BARO sensor when the engine is running. If the input voltage is less than 0.2 V, the PCM determines that the BARO sensor circuit input voltage is low.

P0108 BARO sensor circuit high input

• The PCM monitors the input voltage from the BARO sensor when the engine is running. If the input voltage is more than 4.8 V, the PCM determines that the BARO sensor circuit input voltage is high.

P0111 IAT sensor circuit range/performance problem

• The PCM compares the IAT with the ECT when the engine is running. If the IAT is higher than the ECT by 40 °C {104 °F}, the PCM determines that there is an IAT sensor circuit range/performance problem.

P0112 IAT sensor circuit low input

• The PCM monitors the input voltage from the IAT sensor when the engine is running. If the input voltage is less than 0.1 V, the PCM determines that the IAT sensor circuit input voltage is low.

P0113 IAT sensor circuit high input

• The PCM monitors the input voltage from the IAT sensor when the engine is running. If the input voltage is more than 4.8 V, the PCM determines that the IAT sensor circuit input voltage is high.

P0117 ECT sensor circuit low input

• The PCM monitors the input voltage from the ECT sensor when the engine is running. If the input voltage is less than 0.2 V, the PCM determines that the ECT sensor circuit input voltage is low.

P0118 ECT sensor circuit high input

• The PCM monitors the input voltage from the ECT sensor when the engine is running. If the input voltage is more than 4.8 V, the PCM determines that the ECT sensor circuit input voltage is high.

P0122 TP sensor No.1 circuit low input

• The PCM monitors the input voltage from the TP sensor No.1 when the engine is running. If the input voltage is less than 0.3 V, the PCM determines that the TP sensor No.1 circuit input voltage is low.

P0123 TP sensor No.1 circuit high input

• The PCM monitors the input voltage from the TP sensor No.1 when the engine is running. If the input voltage is more than 4.8 V, the PCM determines that the TP sensor No.1 circuit input voltage is high.

P0125 Insufficient coolant temperature for closed loop fuel control

• The PCM monitors the ECT after cold engine start. If the ECT does not reach the specification in a certain period, the PCM determines that the coolant temperature for closed loop fuel control is insufficient.

P0130 Front HO2S circuit problem

• The PCM monitors the front HO2S impedance when under the front HO2S heater control. If the impedance is more than 500 ohms, the PCM determines that there is a front HO2S circuit problem.

P0131 Front HO2S circuit low voltage

• The PCM monitors the input voltage from the front HO2S and the front HO2S output current when the engine is running. If the input voltage is less than 1.8 V or the output current is less than -5 mA, the PCM determines that the front HO2S circuit voltage is low.

P0132 Front HO2S circuit high voltage

• The PCM monitors the input voltage from the front HO2S and the front HO2S output current when the engine is running. If the input voltage is more than 3.8 V or the output current is more than 5 mA, the PCM determines that the front HO2S circuit voltage is high.

P0133 Front HO2S circuit slow response

• The PCM monitors the front HO2S output current and short term fuel trim (SHRTFT) when the following conditions are met. If the output current response is lower than that expected from the fuel trim, the PCM determines that the front HO2S circuit response is slow.

MONITORING CONDITION
– Front HO2S heater monitor: Completed
– Fuel system loop status: Closed loop fuel control
– Engine speed: 2,000-3,500 rpm
– LOAD: 30.0-50.0 %

P0138 Rear HO2S circuit high voltage

• The PCM monitors the input voltage from the rear HO2S when the engine is running. If the input voltage is more than 1.2 V, the PCM determines that the rear HO2S circuit voltage is high.

P0139 Rear HO2S circuit slow response

• The PCM monitors the rear HO2S inversion cycle period, lean-to-rich response time and rich-to-lean response time when under the open loop fuel control (fuel cut off control). If the average response time is more than the specification, the PCM determines that the rear HO2S circuit response is slow.

P0171 System too lean

• The PCM monitors the short term fuel trim (SHRTFT) and long term fuel trim (LONGFT) when under closed loop fuel control. If the fuel trim is more than the specification, the PCM determines that the system is too lean.

P0172 System too rich

• The PCM monitors the short term fuel trim (SHRTFT) and long term fuel trim (LONGFT) when under closed loop fuel control. If the fuel trim is less than the specification, the PCM determines that the system is too rich.

P0222 TP sensor No.2 circuit low input

• The PCM monitors the input voltage from the TP sensor No.2 when the engine is running. If the input voltage is less than 0.7 V, the PCM determines that the TP sensor No.2 circuit input voltage is low.

P0223 TP sensor No.2 circuit high input

• The PCM monitors the input voltage from the TP sensor No.2 when the engine is running. If the input voltage is more than 4.8 V, the PCM determines that the TP sensor No.2 circuit input voltage is high.

P0300 Random misfire detected

• The PCM monitors eccentric shaft position sensor input signal interval time. The PCM calculates the change of the interval time for each rotor. If the change of interval time exceeds the preprogrammed criteria, the PCM detects a misfire in the corresponding rotor. While the engine is running, the PCM counts the number of misfires that occurred at 200 eccentric shaft revolutions and 1,000 eccentric shaft revolutions and calculates misfire ratio for each eccentric shaft revolution. If the ratio exceeds the preprogrammed criteria, the PCM determines that a misfire, which can damage the catalytic converter or affect emission performance, has occurred.

P0301 Front rotor misfire detected

• The PCM monitors eccentric shaft position sensor input signal interval time. The PCM calculates the change of the interval time for each rotor. If the change of interval time exceeds the preprogrammed criteria, the PCM detects a misfire in the corresponding rotor. While the engine is running, the PCM counts the number of misfires that occurred at 200 eccentric shaft revolutions and 1,000 eccentric shaft revolutions and calculates misfire ratio for each eccentric shaft revolution. If the ratio exceeds the preprogrammed criteria, the PCM determines that a misfire, which can damage the catalytic converter or affect emission performance, has occurred.

P0302 Rear rotor misfire detected

• The PCM monitors eccentric shaft position sensor input signal interval time. The PCM calculates the change of the interval time for each rotor. If the change of interval time exceeds the preprogrammed criteria, the PCM detects a misfire in the corresponding rotor. While the engine is running, the PCM counts the number of misfires that occurred at 200 eccentric shaft revolutions and 1,000 eccentric shaft revolutions and calculates misfire ratio for each eccentric shaft revolution. If the ratio exceeds the preprogrammed criteria, the PCM determines that a misfire, which can damage the catalytic converter or affect emission performance, has occurred.

P0327 KS circuit low input

• The PCM monitors the input voltage from the KS when the engine is running. If the input voltage is less than 1.2 V, the PCM determines that the KS circuit input voltage is low.

P0328 KS circuit high input

• The PCM monitors the input voltage from the KS when the engine is running. If the input voltage is more than 4.0 V, the PCM determines that the KS circuit input voltage is high.

P0335 Eccentric shaft position sensor circuit problem

• The PCM monitors the input signal from the eccentric shaft position sensor when the mass intake airflow amount is more than 2 g/s {0.26 lb/min}. If the input signal is not input, the PCM determines that there is a eccentric shaft position sensor circuit malfunction.

P0336 Eccentric shaft position sensor circuit range/performance problem

• The PCM monitors the input signal from the eccentric shaft position sensor when the engine is running. If the input signal is not the proper pulse number, the PCM determines that there is a eccentric shaft position sensor circuit range/performance problem.

P0410 AIR system problem

• The PCM monitors the front HO2S output current when the AIR control is operating. If the output current is more than the specification, the PCM determines that there is an AIR system problem.

P0420 Catalyst system efficiency below threshold

• The PCM monitors the input voltage from the rear HO2S and the front HO2S output current when the following conditions are met. If the input voltage change is extremely large compared to the output current change, the PCM determines that the catalyst system has deteriorated.

MONITORING CONDITION
– ECT: more than 70 °C {158 °F}
– Catalyst converter temperature: more than 400 °C {752 °F}
– Engine speed: 1,500- 3,500 rpm
– LOAD: 20- 50% (maximum calculated load value varies depending on engine speed.)
– Time with purge control system does not operate: more than 20 s

P0443 Purge solenoid valve circuit problem

• The PCM monitors the purge solenoid valve control voltage when the PCM turns the purge solenoid valve off. If the control voltage is less than 5.8 V, the PCM determines that the purge solenoid valve control circuit voltage is low.

• The PCM monitors the purge solenoid valve control voltage when the PCM turns the purge solenoid valve on. If the control voltage is more than 11.5 V, the PCM determines that the purge solenoid valve control circuit voltage is high.

P0461 Fuel gauge sender unit circuit range/performance problem

• The PCM monitors the fuel tank level difference before and after the PCM-calculated fuel consumption has reached more than 21 L {22.2 US qt, 18.5 Imp qt}. If the difference is less than 5 %, the PCM determines that there is a fuel gauge sender unit circuit range/performance problem.

P0462 Fuel gauge sender unit circuit low input

• The PCM monitors the fuel tank level and input voltage from the fuel gauge sender unit when the engine is running. If the input voltage is less than 2.5 V and fuel tank level is full, the PCM determines that the fuel gauge sender unit circuit input voltage is low.

P0463 Fuel gauge sender unit circuit high input

• The PCM monitors the fuel tank level and input voltage from the fuel gauge sender unit when the engine is running. If the input voltage is more than 2.5 V and fuel tank level is empty, the PCM determines that the fuel gauge sender unit circuit input voltage is high.

P0480 Cooling fan No.1 control circuit problem

• The PCM monitors the cooling fan relay No.1 control voltage when the PCM turns the cooling fan relay No.1 off. If the control voltage is low, the PCM determines that the cooling fan No.1 control circuit voltage is low.

• The PCM monitors the cooling fan relay No.1 control voltage when the PCM turns the cooling fan relay No.1 on. If the control voltage is high, the PCM determines that the cooling fan No.1 control circuit voltage is high.

P0481 Cooling fan No.2 control circuit problem

• The PCM monitors the cooling fan relay No.2 control voltage when the PCM turns the cooling fan relay No.2 off. If the control voltage is low, the PCM determines that the cooling fan No.2 control circuit voltage is low.

• The PCM monitors the cooling fan relay No.2 control voltage when the PCM turns the cooling fan relay No.2 on. If the control voltage is high, the PCM determines that the cooling fan No.2 control circuit voltage is high.

P0500 VSS circuit problem

• The PCM monitors the input signal from the vehicle speed sensor when the following conditions are met. If the input signal is less than 3.7 km/h {2.3 mph}, the PCM determines that there is a VSS circuit malfunction.

MONITORING CONDITION
– Shift lever position: gear is not in neutral position
– Engine speed: more than 2,500 rpm
– LOAD: more than 40.0 %

P0505 Idle air control system problem

• The PCM cannot control idle speed at the target idle speed during the self-test.

P0562 System voltage low (KAM)

• The PCM monitors the battery voltage when the engine is running. If the voltage is less than 2.5 V, the PCM determines that the system voltage is low.

P0564 Cruise control switch input circuit problem

• The PCM monitors the input voltage from the cruise control switch when the engine is running. If the input voltage is less than 3.0 V for more than 2 min, the PCM determines that there is a cruise control switch input circuit problem.

P0571 Brake switch input circuit problem

• The PCM monitors the input signal from brake switch No.1 and brake switch No.2 when the engine is running. If the both input signals remain on or off, the PCM determines that there is a brake switch input circuit problem.

P0601 PCM memory check sum error

• PCM internal memory check sum error.

P0602 PCM programming error

• No configuration data in the PCM.

P0604 PCM random access memory error

• PCM internal random access memory error.

P0610 PCM vehicle options error

• PCM data configuration error.

P0638 Throttle actuator control circuit range/performance problem

• The PCM compares the actual TP with the target TP when the engine is running. If the difference is more than the specification, the PCM determines that there is a throttle actuator control circuit range/performance problem.

P0661 SSV solenoid valve control circuit low

• The PCM monitors the SSV solenoid valve control voltage when the PCM turns the SSV solenoid valve off. If the control voltage is less than 5.8 V, the PCM determines that the SSV solenoid valve control circuit voltage is low.

P0662 SSV solenoid valve control circuit high

• The PCM monitors the SSV solenoid valve control voltage when the PCM turns the SSV solenoid valve on. If the control voltage is more than 11.5 V, the PCM determines that the SSV solenoid valve control circuit voltage is high.

P0703 Brake switch No.1 input circuit problem

• The PCM monitors the input signal from the brake switch No.2 when the following conditions are met. If the input signal does not change while alternately accelerating and decelerating 8 times, the PCM determines that there is a brake switch No.2 input circuit malfunction.

MONITORING CONDITION
– Vehicle speed: decelerating more than 30 km/h {19 mph} to 0 km/h {0 mph}
– Deceleration: more than 4 km/h {2 mph} per s

P0704 CPP switch input circuit problem

• The PCM monitors the input signal from the CPP switch when the vehicle speed is more than 30 km/h {19 mph}. If the input signal does not change while alternately accelerating and decelerating 10 times, the PCM determines that there is a CPP switch input circuit malfunction.

P0850 Neutral switch input circuit problem

• The PCM monitors the input signal from the neutral switch when the vehicle is running. If the input signal does not change while alternately running more than 30 km/h {19 mph} 8 times, the PCM determines that there is a neutral switch input circuit malfunction.

P1260 Immobilizer system problem

• The keyless unit detects an immobilizer system malfunction.

P1574 TP sensor output incongruent

• The PCM compares the TP from TP sensor No.1 with the TP from TP sensor No.2 when the engine is running. If the difference is more than the specification, the PCM determines that the TP sensor outputs are incongruent.

P1577 APP sensor output incongruent

• The PCM compares the APP from APP sensor No.1 with the APP from APP sensor No.2 when the engine is running. If the difference is more than the specification, the PCM determines that the APP sensor outputs are incongruent.

P1686 Metering oil pump control circuit low flow side problem

• The PCM monitors the input signal from the metering oil pump switch when the metering oil pump stepping motor is more than the standard step. If the input signal is off, the PCM determines that the metering oil pump control circuit has a problem on the low flow side.

P1687 Metering oil pump control circuit high flow side problem

• The PCM monitors the input signal from the metering oil pump switch when the metering oil pump stepping motor is less than the standard step. If the input signal is on, the PCM determines that the metering oil pump control circuit has a problem on the high flow side.

P1688 Metering oil pump control circuit initial check problem

• The PCM monitors the input signal from the metering oil pump switch when the metering oil pump stepping motor initial check is operating. If the input signal is on, the PCM determines that there is a metering oil pump control circuit initial check problem.

P2006 APV motor control circuit IC problem

• APV motor control IC error.

P2008 APV motor control circuit/open

• The PCM monitors the APV motor control current when the engine is running. If the control current is less than 0.1 A or more than 10 A, the PCM determines that there is an APV motor control open circuit.

P2096 Target A/F feedback system too lean

• The PCM monitors the target A/F fuel trim when under the target A/F feedback control. If the fuel trim is more than the specification, the PCM determines that the target A/F feedback system is too lean.

P2097 Target A/F feedback system too rich

• The PCM monitors the target A/F fuel trim when under the target A/F feedback control. If the fuel trim is less than the specification, the PCM determines that the target A/F feedback system is too rich.

P2101 Drive-by-wire relay control circuit problem

• The PCM monitors the input voltage from the drive-by-wire relay when the PCM turns the drive-by-wire relay on. If the input voltage is less than 5.0 V, the PCM determines that the drive-by-wire relay control circuit voltage is low.

• The PCM monitors the input voltage from the drive-by-wire relay when the PCM turns the drive-by-wire relay off. If the input voltage is more than 5.0 V, the PCM determines that the drive-by-wire relay control circuit voltage is high.

P2106 Throttle actuator control system-forced limited power

• The PCM monitors the throttle actuator control current when the ignition switch is on. If the control current is less than 8 A or more than 11 A, the PCM determines that the throttle actuator control system is under forced limited power.

P2107 Throttle actuator control module processor error

• Throttle actuator control module internal processor error.

P2108 Throttle actuator control module performance error

• Throttle actuator control module internal communication error.

P2109 TP sensor minimum stop range/performance problem

• The PCM monitors the minimum TP when the closed TP learning is completed. If the TP is less than 11.5 % or more than 24.3 %, the PCM determines that there is a TP sensor minimum stop range/performance problem.

P2112 Throttle actuator control system range/performance problem

• The PCM monitors the throttle actuator control duty ratio when the engine is running. If the duty ratio is more than 95 %, the PCM determines that there is a throttle actuator control system range/performance problem.

P2119 Throttle actuator control throttle body range/performance problem

• The PCM compares the TP with default TP when the ignition switch is turned off. If the TP is higher than the default TP, the PCM determines that there is a throttle actuator control throttle body range/performance problem.

P2122 APP sensor No.1 circuit low input

• The PCM monitors the input voltage from the APP sensor No.1 when the engine is running. If the input voltage is less than 0.3 V, the PCM determines that the APP sensor No.1 circuit input voltage is low.

P2123 APP sensor No.1 circuit high input

• The PCM monitors the input voltage from the APP sensor No.1 when the engine is running. If the input voltage is more than 4.8 V, the PCM determines that the APP sensor No.1 circuit input voltage is high.

P2127 APP sensor No.2 circuit low input

• The PCM monitors the input voltage from the APP sensor No.2 when the engine is running. If the input voltage is less than 0.3 V, the PCM determines that the APP sensor No.2 circuit input voltage is low.

P2128 APP sensor No.2 circuit high input

• The PCM monitors the input voltage from the APP sensor No.2 when the engine is running. If the input voltage is more than 4.8 V, the PCM determines that the APP sensor No.2 circuit input voltage is high.

P2135 TP sensor No.1/No.2 voltage correlation problem

• The PCM compares the input voltage from TP sensor No.1 with the input voltage from TP sensor No.2 when the engine is running. If the difference is more than the specification, the PCM determines that there is a TP sensor No.1/No.2 voltage correlation problem.

P2136 TP sensor No.1/No.3 voltage correlation problem

• The PCM compares the input voltage from TP sensor No.1 with the input voltage from TP sensor No.3 (calculation value in PCM) when the engine is running. If the difference is more than the specification, the PCM determines that there is a TP sensor No.1/No.3 voltage correlation problem.

P2138 APP sensor No.1/No.2 voltage correlation problem

• The PCM compares the input voltage from APP sensor No.1 with the input voltage from APP sensor No.2 when the engine is running. If the difference is more than the specification, the PCM determines that there is an APP sensor No.1/No.2 voltage correlation problem.

P2195 Front HO2S signal stuck lean

• The PCM monitors the front HO2S output current when the following conditions are met. If the average output current is more than 1.2 A for 25 s, the PCM determines that the front HO2S signal remains lean.

MONITORING CONDITION
– ECT: more than 70 °C {158 °F}
– Engine speed: 1,000-3,200 rpm
– MAF amount: 6-80 g/s {0.80-10.58 lb/min}
– Target A/F feedback system status: feedback control
– Input voltage from the rear HO2S: more than 0.7 V

P2196 Front HO2S signal stuck rich

• The PCM monitors the front HO2S output current when the following conditions are met. If the average output current is less than 0.8 A for 25 s, the PCM determines that the front HO2S signal remains rich.

MONITORING CONDITION
– ECT: more than 70 °C {158 °F}
– Engine speed: 1,000-3,200 rpm
– MAF amount: 6-80 g/s {0.80-10.58 lb/min}
– Target A/F feedback system status: feedback control
– Input voltage from the rear HO2S: less than 0.2 V

P2257 AIR pump relay control circuit low

• The PCM monitors the AIR pump relay control voltage when the AIR pump is not operating. If the control voltage is less than 5.8 V, the PCM determines that the AIR pump relay control circuit voltage is low.

P2258 AIR pump relay control circuit high

• The PCM monitors the AIR pump relay control voltage when the AIR pump is operating. If the control voltage is more than 11.5 V, the PCM determines that the AIR pump relay control circuit voltage is high.

P2259 AIR solenoid valve control circuit low

• The PCM monitors the AIR solenoid valve control voltage when the AIR pump is not operating. If the control voltage is less than 5.8 V, the PCM determines that the AIR solenoid valve control circuit voltage is low.

P2260 AIR solenoid valve control circuit high

• The PCM monitors the AIR solenoid valve control voltage when the AIR pump is operating. If the control voltage is more than 11.5 V, the PCM determines that the AIR solenoid valve control circuit voltage is high.

P2270 Rear HO2S signal stuck lean

• The PCM monitors the input voltage from the rear HO2S when the following conditions are met. If the input voltage is more than 0.9 V for 40 s, the PCM determines that the rear HO2S signal remains lean.

MONITORING CONDITION
– ECT: more than 70 °C {158 °F}
– Engine speed: more than 1,500 rpm
– MAF amount: more than 10 g/s {1.32 lb/min}
– Short term fuel trim: -20-20 %
– Long term fuel trim: -15-15 %
– Target A/F feedback system status: feedback control

P2271 Rear HO2S signal stuck rich

• The PCM monitors the input voltage from the rear HO2S when the following conditions are met. If the input voltage is less than 0.4 V for 40 s, the PCM determines that the rear HO2S signal remains rich.

MONITORING CONDITION
– ECT: more than 70 °C {158 °F}
– Engine speed: more than 1,500 rpm
– MAF amount: more than 10 g/s {1.32 lb/min}
– Short term fuel trim: -20-20 %
– Long term fuel trim: -15-15 %
– Target A/F feedback system status: feedback control

P2502 Charging system voltage problem

• The PCM monitors the generator output voltage and the battery voltage when the engine is running. If the generator output voltage is more than 16.9 V and the battery voltage is less than 10.9 V, the PCM determines that there is a charging system voltage malfunction.

P2503 Charging system voltage low

• The PCM monitors the generator output voltage when the engine is running. If the generator output voltage is less than 8.5 V while the PCM needs more than 19.5 A from the generator, the PCM determines that the charging system voltage is low.

P2504 Charging system voltage high

• The PCM monitors the generator output voltage and the battery voltage when the engine is running. If the generator output voltage is more than 18.4 V or the battery voltage is more than 15.9 V, the PCM determines that the charging system voltage is high.