LEMON Manuals: Even more car manuals for everyone
Home >> Chevrolet >> 2001 >> Venture Base, Van Passenger >> Repair and Diagnosis >> External Pages >> Different car >> Section 16 (HVAC Systems - Automatic) >> Diagnostic Tests >> DTC P1545 & P1546: A/C Clutch Relay Control Circuit

DTC P1545 & P1546: A/C Clutch Relay Control Circuit

WARNING: This page is about a different car, the 2002 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: DTC P1545 applies to 4.0L V8. DTC P1546 applies to 3.5L V6.
  1. Perform diagnostic system check. See DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing system check, go to next step.
  2. Connect scan tool. Start engine. Using scan tool, command A/C COMPRESSOR CLUTCH RELAY ON and OFF. If A/C clutch relay turns ON and OFF with each command, inspect wiring and connectors for intermittent loose wires and/or poor connections. Ensure PCM engine grounds are clean and tight. If A/C compressor relay does not turn on and off, go to next step.
  3. Turn ignition off. Disconnect A/C clutch relay. Turn ignition on. Connect test light between ground and terminal No. 2 of A/C clutch relay socket. If test light illuminates, go to next step. If test light does not illuminate, repair ignition voltage circuit of compressor clutch relay. Go to step  8.
  4. Connect test light between terminal No. 2 of A/C clutch relay and IGN fuse E (10-amp). Using scan tool, command A/C COMPRESSOR CLUTCH RELAY ON and OFF. If test light turns off and on with each command, check for loose wires and poor connections at A/C clutch relay. If wiring and connectors are okay, replace A/C clutch relay. Go to step  8. If test light does not turn off and on with each command, go to next step.
  5. If test light remained illuminated with each command, go to step  7. If test light remained off with each command, go to next step.
  6. Check for open or short to voltage between ground and terminal C11 (Dark Green wire) of A/C clutch relay harness connector. If problem exists, repair open or short to voltage in Dark Green wire between terminal C11 of A/C clutch relay and terminal "A" of A/C compressor clutch harness connector. Go to step  8. If problem does not exist, check for loose wires and poor connections at PCM. Repair as necessary. Go to step  8. If wiring and connectors are okay, replace PCM. See POWERTRAIN CONTROL MODULE in REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE. Go to step  8.
  7. Check for short to ground between ground and terminal C11 (Dark Green wire) of A/C clutch relay harness connector. If problem exists, repair as necessary. Go to next step. If problem does not exist, check for loose wires and poor connections at PCM. Repair as necessary. Go to next step. If wiring and connectors are okay, replace PCM. See POWERTRAIN CONTROL MODULE in REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE. Go to next step.
  8. Use scan tool to clear DTCs. Operate vehicle and verify that DTCs do not reset. If DTCs reset, return to step  2. If DTCs do not reset, system is okay.
scientia non olet · About LEMON Manuals