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Home >> Suzuki >> 2006 >> Reno Base, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> Engine Control Systems >> Engine Performance - DTC P0532 - P1166 >> DTC P0641: 5 Volt Reference 1 Circuit >> Troubleshooting
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DTC P0641: 5 Volt Reference 1 Circuit: Troubleshooting

TROUBLESHOOTING CHART

Step Action Value(s) Yes No
1 Did you perform the Diagnostic System Check? - Go to Step 2 Go to On-Board Diagnostic (OBD II) System Check
2
  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn the ignition OFF for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?
- Go to Step 3 Go to Diagnostic Aids
3
  1. Turn the ignition OFF.
  2. Disconnect the Throttle Position (TP) sensor.
  3. Turn the ignition ON, with the engine OFF.
  4. Measure the voltage from the 5 volt reference circuit of the TP sensor 1 to a good ground with a DMM.
  5. Repeat the above steps for the following devices connected to the 5 volt reference 1 circuit, one at a time.
    • TP sensor 2
    • APP sensor 1

Is the voltage within the specified range?
4.8 - 5.2 V Go to Step 7 Go to Step 4
4 Is the voltage measured in the previous step more than the specified value? 5.2 V Go to Step 5 Go to Step 6
5 Test the 5 volt reference circuit for a short to voltage.
Did you find and correct the condition?
- Go to Step 9 Go to Step 8
6 Test the 5 volt reference circuit for a short to ground or any sensor low reference circuit.
Did you find and correct the condition?
- Go to Step 9 Go to Step 8
7 Replace the affected sensors.
Did you complete the replacement?
- Go to Step 9 -
8 Replace the ECM.
Did you complete the replacement?
- Go to Step 9 -
9
  1. Clear the DTCs with a scan tool.
  2. Turn the ignition OFF for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?
- Go to Step 2 Go to Step 10
10 Check if any additional DTCs are set.
Are any DTCs displayed that have not been diagnosed?
- Go to applicable DTC table System OK