DTC 09: ER20

id0902f6818500

DTC 09: Er20

Power supply circuit of base unit

DETECTION CONDITION

• When the voltage at terminals 1B and 1R is 8.5 V or less, or 16 V or more.

POSSIBLE CAUSE

• Battery malfunction
• Power supply wiring harness malfunction

Diagnostic procedure

Step

Inspection

Action

1
INSPECT FUSE
• Remove the ROOM 15 A fuse and MIRROR 7.5 A fuse.
• Is the fuse normal?
Yes
Go to the next step.
No
Replace the fuse.
2
INSPECT BATTERY
• Measure battery voltage.
• Is voltage 8.5 V-16 V?
Yes
Go to the next step.
No
Battery malfunction
Inspect the charge/discharge system.
3
INSPECT WIRING HARNESS BETWEEN BATTERY AND FUSE BLOCK
• Turn the ignition switch to the ACC or ON position.
• Measure voltage at fuse block terminals AG and AH.
• Is voltage 8.5 V-16 V?
Yes
Go to the next step.
No
Repair the wiring harness between the battery and fuse block.
4
INSPECT WIRING HARNESS BETWEEN FUSE BLOCK AND BASE UNIT
• Turn the ignition switch to the LOCK position.
• Install the ROOM 15 A fuse and MIRROR 7.5 A fuse.
• Turn the ignition switch to the ACC position.
• Measure voltage at the audio unit connector terminal 1B and 1R.
• Is voltage 8.5 V-16 V?
Yes
Go to the next step.
No
Repair the wiring harness between the fuse block connector and base unit.
5
INSPECT BASE UNIT
• Turn the ignition switch to the ACC or ON position and hold for 30 s or more.
• DTC 09: Er20 displayed?
Yes
Replace the base unit.
No
Troubleshooting completed.