Testing the Serial Data Circuits for an Open/High Resistance
- Connect the harness connectors at the control module that was previously disconnected.
- Ignition OFF, disconnect the harness connectors with the BECM dedicated serial data circuits at another control module that is not communicating, in the direction of the open circuit.
- Ignition OFF and all vehicle systems OFF, all keys at least 3 meters away from vehicle, all access doors closed. It may take up to 2 minutes for all vehicle systems to power down. Test for greater than 130 Ω between each pair of BECM dedicated serial data circuits at the control module connector that was just disconnected. Verify that one pair of BECM dedicated serial data circuits are greater than 130 Ω.
- If each pair of BECM dedicated serial data circuits is less than the specified range, replace the control module that was just disconnected.
- Repeat step 1 until one of the following conditions are isolated:
- An open/high resistance on the BECM dedicated serial data circuit between 2 control modules or splice packs, if equipped
- An open/high resistance on the BECM dedicated serial data circuit between a control module and a terminating resistor
- An open/high resistance terminating resistor