Message Systems

9081-LOST COMMUNICATION WITH RAIN LIGHT SENSOR (PRIVATE BUS)

For a complete wiring diagram Consult Diagrams/Electrical.

- When Monitored:
Continuously with the ignition on.

- Set Condition:
The Roof Control Module (RCM) detects failure to reply from the Rain/Light Sensor (RLS) for at least 13 consecutive communication cycles.





Diagnostic Test

1. DTC IS ACTIVE
Turn the ignition on.
With the scan tool, read RCM DTC's.
Is the DTC status Active at this time?

Yes

- Go to 2

No

- The condition that caused this symptom is currently not present. Check for an intermittent condition by inspecting the related wiring harness for chafed, pierced, pinched, and partially broken wires. Also, inspect the related connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals. Repair as necessary.
- Perform BODY VERIFICATION TEST - VER 1. Verification Tests.

2. RAIN/LIGHT SENSOR (RLS)
Turn the ignition off.

NOTE: After replacing the Rain/Light Sensor, perform the Control Unit Adaptations setup routine.

Replace the Rain/Light Sensor (RLS) with a known good sensor.
Turn the ignition on.
With the scan tool, erase all DTC's.
With the scan tool, check for active DTC's.
Does the scan tool display this DTC as active?

Yes

- Check the data line from the Roof Control Module (RCM) to the Rain/Light Sensor along with inspecting the related wiring harness for chafed, pierced, pinched, and partially broken wires. Also, inspect the related connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals. If wiring and connectors are ok, replace the Roof Control Module (RCM).
- Perform BODY VERIFICATION TEST - VER 1. Verification Tests.

No

- Test Complete.