No Response From Radio
NOTE:
After making any repairs, perform BODY VERIFICATION TEST
under VERIFICATION TESTS.
- Turn ignition on. Using scan tool, attempt to communicate with Occupant Restraint Controller (ORC) and Body Control Module (BCM). If scan tool identifies or communicates with any module, go to next step. If scan tool does not identify or communicate with any module, go to PCI BUS COMMUNICATION FAILURE .
- Turn ignition off. Remove radio and disconnect electrical connectors. See RADIO under REMOVAL & INSTALLATION. Turn ignition on. Using a test light connected to ground, probe radio connector C1 terminal No. 6 (Dark Blue/Pink wire). See Fig 1 . If test light illuminates, go to next step. If test light does not illuminate, fuse No. 5 (20-amp) located in Intelligent Power Module (IPM). See Figure . If fuse is okay, repair open or short to ground in Dark Blue/Pink wire.
- Turn ignition off. Using a test light connected to ground, probe radio connector C1 terminal No. 7 (Gray/Red wire). If test light illuminates, go to next step. If test light does not illuminate, check fuse No. 14 (15-amp) located in IPM. If fuse is okay, repair open or short to ground in Gray/Red wire.
- Disconnect radio ground wire attached to rear of radio. Using DVOM, measure resistance between ground wire and ground. If resistance is 5 ohms or less, go to next step. If resistance is greater than 5 ohms, repair or replace radio ground wire.
- Obtain Scope Input Cable (CH7058), Cable To Probe Adapter (CH7062) and Red and Black test probes. Connect scope input cable to channel 1 connector on scan tool. Connect Red and Black test probes and probe adapter to scope input cable. Select STANDALONE on scan tool. Select LAB SCOPE then LIVE DATA. Select 12V SQUARE WAVE. Press F2 for scope then enter to select channel. Press F2 again and use down arrow to set voltage range to 20 volts. Press F2 again to complete. Connect Black probe to ground and Red probe to radio connector C3 terminal No. 1 (White/Violet wire). Turn ignition on. Monitor scope on scan tool. If voltage pulses between zero and 7.5 volts, go to next step. If voltage does not pulse between zero and 7.5 volts, repair open in White/Violet wire (PCI bus circuit) between radio and diagnostic junction port terminal No. 3. See Figure .
- Replace radio. See RADIO under REMOVAL & INSTALLATION.