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DTC Troubleshooting

NOTE: Before this trouble shooting is performed, read the precautions for DTC troubleshooting referring to PRECAUTIONS FOR DTC TROUBLESHOOTING .
DTC TROUBLESHOOTING CHART

Step Action YES NO
1  Was "Engine and Emission Control System Check" performed?  Go to Step 2. Go to ENGINE AND EMISSION CONTROL SYSTEM CHECK .
2  A/C compressor relay signal check 
  1. Connect scan tool to DLC with ignition switch turned OFF.
  2. Start engine and then operate A/C system.
  3. Check A/C compressor relay control signal of "A/C Comp Relay" under "Data List" displayed on scan tool.
    • A/C switch is at ON position and blower selector is other than OFF position: "ON".
    • A/C switch is at OFF position and blower selector is at OFF position: "OFF".

Does "A/C Comp Relay" signal correctly? 		 Intermittent trouble. Check for intermittent referring to INTERMITTENT AND POOR CONNECTION INSPECTION . Go to Step 3.
3  A/C compressor relay control signal check 
  1. Disconnect connectors from ECM with ignition switch turned OFF.
  2. Check that A/C compressor relay control signal circuit voltage between ECM connector and vehicle body ground.
    • Ignition switch is at "ON" position: 10 - 14 V
    • Ignition switch is at "OFF" position: 0 - 1 V

Is it in good condition? 		 Substitute a known-good ECM and recheck. Go to Step 4.
4  A/C compressor relay power supply voltage check 
  1. Turn ignition switch to OFF position.
  2. Remove A/C compressor relay.
  3. Check that A/C compressor relay power supply voltage between A/C compressor relay connector and vehicle body ground.
    • Ignition switch is at "ON" position: 10 - 14 V
    • Ignition switch is at "OFF" position: 0 - 1 V

Is it in good condition? 		 Go to Step 5. Repair or replace power supply circuit of A/C compressor relay.
5  A/C compressor relay check 
Check A/C compressor relay for operation referring to A/C COMPRESSOR RELAY INSPECTION .
Is it in good condition? 		 Control signal circuit of A/C compressor relay is open or short. If circuit is OK, substitute a known-good ECM and recheck. Replace A/C compressor relay.
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