Code B120, Twilight Delay & B122, Panel Dimming (Simultaneously): Notes
Since both potentiometers use same power and ground, problem is in power or ground circuit when both Codes B120 and B122 are stored.
NOTE:
Test numbers refer to numbers on diagnostic chart.
- Checks to see if open or grounded circuit reading is due to circuit or switch. If voltage can be read across circuits No. 705 and 736 after disconnecting switch assembly, BCM and wiring are okay.
- Check for 5-volt reference at switch. If 5 volts are present, circuit No. 736 is open. If circuit No. 736 is open, open will be between terminal B4 on left switch and cavity B2 on dash-IP transition connector.
- If circuit No. 705 is suspected of being grounded, remove HVAC programmer and BCM connectors prior to making ground check.
- If there is no ground in circuit No. 705, replace HVAC programmer or BCM.