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Home >> Suzuki >> 2005 >> Reno LX, Automatic >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine General Information And Diagnosis >> Diagnostic Information and Procedures >> DTC P0645 A/C Clutch Output Circuit Fault >> Troubleshooting
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DTC P0645 A/C Clutch Output Circuit Fault: Troubleshooting

TROUBLESHOOTING CHART

Step Action Value(s) Yes No
1 Perform an On-Board Diagnostic (OBD II) System Check.
Is the system check complete?		 - Go to Step 2 Go to "ON-BOARD DIAGNOSTIC (OBD II) SYSTEM CHECK :"
2
  1. Install the scan tool.
  2. Start the engine and idle with the A/C ON.

Does the A/C clutch operate properly?		 - Go to Step 3 Go to Step 5
3 Using the scan tool, monitor the A/C request display on the scan tool.
Does the scan tool indicate A/C request as ON?		 - Go to Step 4 Go to Step 8
4
  1. Turn the engine OFF, ignition ON.
  2. Review the Freeze Frame and/or Failure Records data for this DTC and note parameters.
  3. Turn the ignition OFF for 15 seconds.
  4. Start the engine and operate the vehicle within the conditions required for this diagnostic to run, and as close to the conditions recorded in Freeze Frame/Failure Records as possible.

Does the scan tool indicate that this diagnostic failed this ignition?		 - Go to Step 5 Go to "DIAGNOSTIC AIDS :"
5
  1. Turn the ignition OFF.
  2. Disconnect the A/C clutch relay.
  3. Turn the ignition ON, engine OFF.
  4. Probe the ignition feed circuit at the A/C relay terminal 86 with a test light to ground.

Does the test light illuminate?		 - Go to Step 6 Go to Step 9
6 Using a Digital Voltmeter (DVM), probe the resistance between the terminals 86 and 85 on the compressor relay.
Is the resistance around the specified value?		 98 Ω Go to Step 7 Go to Step 8
7
  1. Ignition OFF.
  2. Disconnect the engine control module (ECM) connector from the ECM.
  3. Using a DVM, probe the resistance between terminal connector K29 and 85.

Is the resistance equal to the specified value?		 0Ω Go to Step 10 Go to Step 11
8 Replace the A/C compressor relay.
Is the repair complete?		 - Go to Step 12 -
9 Repair the open or short to ground in the ignition feed circuit.
Is the repair complete?		 - Go to Step 12 -
10
  1. Turn the ignition OFF.
  2. Replace the ECM.

Is the repair complete?		 - Go to Step 12 -
11 Repair the open or short to voltage in the A/C output circuit.
Is the repair complete?		 - Go to Step 12 -
12
  1. Using the scan tool, clear the Diagnostic Trouble Codes (DTCs).
  2. Start the engine and idle at normal operating temperature.
  3. Operate the vehicle within the conditions for setting this DTC as specified in the supporting text.

Does the scan tool indicate that this diagnostic ran and passed?		 - Go to Step 13 Go to Step 2
13 Check if any additional DTCs are set.
Are any DTCs displayed that have not been diagnosed?		 - Go to APPLICABLE DTC TABLE  System OK
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