B106B-REAR DEFROST CONTROL CIRCUIT LOW (ATC)
For a complete wiring diagram Refer to Section 8W.
- When Monitored:
With ignition on.
- Set Condition:
If the EBL output turned off and the (C115) Rear Window Defogger Relay Control circuit is either shorted to ground or open.
| Possible Causes |
| (C115) REAR WINDOW DEFOGGER RELAY CONTROL CIRCUIT SHORTED TO GROUND |
| (C115) REAR WINDOW DEFOGGER RELAY CONTROL CIRCUIT OPEN |
| REAR WINDOW DEFOGGER
RELAY |
| A/C HEATER CONTROL |
NOTE: This DTC must be active for the results of this test to be valid. Do not perform this test if this DTC is stored. Refer to HVAC System Test (ATC) for stored DTC test procedures.
Diagnostic Test
1. INSTALL A SUBSTITUTE REAR WINDOW DEFOGGER RELAY & THEN CHECK FOR DTC B106B–REAR DEFROST CONTROL CIRCUIT LOW
Turn the ignition on.
Verify that the EBL mode switch is off.
Turn the ignition off.
Install a substitute Rear Window Defogger Relay.
Turn the ignition on.
With the scan tool, erase HVAC DTCs.
Turn the ignition off, wait 10 seconds, and turn the ignition on.
With the scan tool, read HVAC DTCs.
Does the scan tool display: B106B–REAR DEFROST CONTROL CIRCUIT LOW?
Yes
- Go To 2
No
- Replace the original Rear Window Defogger Relay in accordance with the Service Information.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
2. CHECK (C115) REAR WINDOW DEFOGGER RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND
Turn the ignition off.
Remove the substitute Rear Window Defogger Relay.
Disconnect the A/C Heater Control C1 harness connector.
Measure the resistance of the (C115) Rear Window Defogger Relay Control circuit between ground and the A/C Heater Control C1 harness connector.
Is the resistance below 10k ohms?
Yes
- Repair the (C115) Rear Window Defogger Relay Control circuit for a short to ground. Reinstall the original Rear Window Defogger Relay.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
No
- Go To 3
3. CHECK (C115) REAR WINDOW DEFOGGER RELAY CONTROL CIRCUIT FOR AN OPEN
Measure the resistance of the (C115) Rear Window Defogger Relay Control circuit between the Rear Window Defogger Relay connector terminal 85 in the JB and the A/C Heater Control C1 harness connector.
Is the resistance below 5.0 ohms?
Yes
- Replace the A/C Heater Control in accordance with the Service Information. Reinstall the original Rear Window Defogger Relay.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
No
- Repair the (C115) Rear Window Defogger Relay Control circuit for an open. Reinstall the original Rear Window Defogger Relay.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).