MD C45-85 IP Gauges / Radio Inoperative -cluster display IPC instrument LOC panel

When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.

Some dealers and customers have reported a condition with instrument cluster gauges inoperative and the radio displays LOC with all other systems functioning properly.

This condition is most commonly the result of low system voltage, discharged battery, improper grounds, loose electrical connectors and improper terminal contacts.

First make sure the battery is fully charged, the charging system is functioning properly and electrical grounds make good contact. Then perform the following steps in sequence.

1. Turn the key to the off position.
2. Tilt the hood and remove all the red marked 10AMP fuses, including the PCM-B fuse, from the main fuse block.
3. After one (1) minute replace all the 10 AMP fuses and start the engine.

This process allows the on-board Class 2 electronic modules to power down and be ready to receive the correct electronic VIN signal message on the next key on power up cycle.

If this process does not correct the condition, it will be necessary to check the following items:

1. Connect the Tech 2 and check for Loss of Communication DTCs
2. Terminal pin contacts for the IP Cluster
3. Gateway module connections on C65-85 (Family 3) models
4. IP wire harness makes contact and chafes on the dash support casting (mag beam)
5. Reprogram the radio security module

Contact Medium Duty Truck Technical Assistance for additional diagnostic assistance.

Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance. This diagnostic approach was developed for the vehicle with the VIN you entered and should not be automatically be used for other vehicles with similar symptoms.

(03 Chevrolet Kodiak/GMC Topkick Medium Duty Conventional Cab C45-85 Models)