DTC 09:ER20


BHE090266900W06

DTC 09:Er20

Power supply circuit of base unit

DETECTION CONDITION

• Voltage detected at base unit terminals 1B and 1R is less than 8.5 V, or more than 16 V (must not be 16V).

POSSIBLE CAUSE

• Weak battery
• Malfunction in wiring harness between battery and base unit

Diagnostic procedure

STEP

INSPECTION

ACTION

1
Remove the ROOM 15 A fuse and ACC 7.5 A fuse.
Are the fuses normal?
Yes
Go to the next step.
No
Replace the fuse.
2
Measure the battery voltage.
Is the voltage between 8.5-16 V?
Yes
Go to the next step.
No
Battery malfunction
Inspect the charge/discharge system.
3
Measure the voltage between fuse block terminals 1B and 2F.
Is the voltage between 8.5-16 V?
Yes
Go to the next step.
No
Inspect fuses, ACC relay and related wiring harnesses between the battery and fuse block.
• If there is any malfunction, repair or replace the applicable part.
4
Install the ROOM 15 A fuse and ACC 7.5 A fuse.
Turn the ignition switch to the ACC position.
Measure the voltage at the audio unit connector terminals 1B and 1R.
Is the voltage between 8.5-16 V?
Yes
Go to the next step.
No
Repair the wiring harness between the fuse block and base unit.
5
Turn the ignition switch to the ACC or ON position and hold for 30 s or more.
Is DTC 09: Er20 displayed?
Yes
Replace the base unit.
No
DTC troubleshooting completed.