Test 3
- Ensure ignition is off. Check continuity in communication line (Red/Yellow wire) between passenger's multiplex control unit Gray 26-pin connector terminal A9 and driver's multiplex control unit Gray 26-pin connector terminal B22. If continuity does not exist, check for open in Red/Yellow wire. If continuity exists, go to next step.
- Turn ignition on. Using a voltmeter, check communication line voltage at passenger's multiplex control unit Gray 26-pin connector terminal A9 (Red/Yellow wire). Voltage should read 4.8-6.0 volts. If voltage is as specified, replace passenger's multiplex control unit with a known-good unit and retest system. If system still does not operate properly, replace driver's multiplex control unit with a known-good unit and retest system. If voltage is not as specified, go to next step.
- If voltage is more than 6.0 volts, check for short in Red/Yellow wire and for poor connection or faulty circuit at receiver unit. See WIRING DIAGRAMS . If voltage is less than 4.8 volts, check for short to ground and for poor connection or faulty circuit at transmitter unit.