Pinpoint Test H: The Air Conditioning (A/C) Is Inoperative - Defrost and Floor/Defrost Modes Only
Climate Control System
Pinpoint Tests
Pinpoint Test H: The Air Conditioning (A/C) is Inoperative - Defrost and Floor/Defrost Modes Only
Refer to Wiring Diagram Set 54, Manual Climate Control System for schematic and connector information. Diagrams By Number
Normal Operation
Under normal operation, the function selector switch is grounded. When the switch is closed, ground is provided to Generic Electronic Module (GEM) defrost circuit input from the function selector switch.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Function selector switch
- GEM
PINPOINT TEST H: THE AIR CONDITIONING (A/C) IS INOPERATIVE - DEFROST AND FLOOR/DEFROST MODES ONLY
NOTE: Before carrying out the following test, diagnose any PCM, GEM or Instrument Cluster (IC) DTCs.
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H1 CHECK THE DEFROST GEM PID
- Start the engine.
- Enter the following diagnostic mode on the scan tool: DEFROST GEM PID .
- With the engine running, place the blower motor switch in the lowest position.
- Place the function selector switch to the DEFROST position.
- Does the DEFROST GEM PID read ACTIVE?
Yes
GO to H5.
No
GO to H2.
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H2 CHECK CIRCUIT 91-FA20 (BK/YE) FOR GROUND
- Disconnect: Function Selector Switch C294 .
- Measure the resistance between function selector switch C294-1, circuit 91-FA20 (BK/YE), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to H3.
No
REPAIR circuit 91-FA20 (BK/YE) for an open. TEST the system for normal operation.
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H3 CHECK THE FUNCTION SELECTOR SWITCH
- Start the engine.
- Place the blower motor switch in the lowest position.
- Connect a fused jumper between function selector switch C294-1, circuit 91-FA20 (BK/YE), harness side and C294-3, circuit 91S-FA20 (BK/YE), harness side.
- Does the A/C compressor operate?
Yes
INSTALL a new function selector switch. TEST the system for normal operation.
No
GO to H4.
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H4 CHECK CIRCUIT 91S-FA20 (BK/YE) FOR AN OPEN
- Ignition OFF.
- Disconnect: GEM C201C .
- Measure the resistance between function selector switch C294-3, circuit 91S-FA20 (BK/YE), harness side and GEM C201C-22, circuit 91S-FA20 (BK/YE), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to H5.
No
REPAIR circuit 91S-FA20 (BK/YE) for an open. TEST the system for normal operation.
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H5 CHECK THE GEM CONNECTION
- Clear the DTCs.
- Disconnect all the GEM connectors.
- Check for:
- corrosion.
- pushed-out pins.
- incorrectly seated connector.
- Connect and correctly seat all the GEM connectors.
- Operate the system.
- Does the concern return?
Yes
INSTALL a new GEM. REFER to Body Control Systems. TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
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