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Home >> Chevrolet >> 2002 >> Blazer 4D Utility, 4WD, Part Time >> Repair and Diagnosis >> External Pages >> Different car >> Section 1015 (Engine Controls Diagnosis - 4.3L (DTCS P0641-P1381)) >> Diagnosis >> DTC P0641 >> Conditions for Clearing the MIL/DTC

Conditions for Clearing the MIL/DTC

WARNING: This page is about a different car, the 2004 GMC Sierra and 2004 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
DTC P0641

Step Action Values Yes No
Schematic Reference:  Engine Controls Schematics 
Connector End View Reference:  Engine Controls Connector End Views  or  Powertrain Control Module (PCM) Connector End Views 
1 Did you perform the Diagnostic System Check-Engine Controls? - Go to Step 2  Go to Diagnostic System Check - Engine Controls
2
  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running 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 Intermittent Conditions
3
  1. Turn OFF the ignition.
  2. Disconnect throttle position (TP) sensor.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure the voltage from the 5-volt reference circuit of the TP sensor to a good ground with a DMM. Refer to Circuit Testing in Wiring Systems.
Is the voltage within the specified range?
4.8-5.2 V Go to Step 5  Go to Step 4 
4 Is the voltage more than the specified value? 5.2 V Go to Step 8  Go to Step 6 
5
  1. Connect the TP sensor.
  2. Disconnect the manifold absolute pressure (MAP) sensor.
  3. Measure the voltage from the 5-volt reference circuit of the MAP sensor to a good ground with a DMM. Refer to Circuit Testing in Wiring Systems.
Is the voltage within the specified range?
4.8-5.2 V Go to Intermittent Conditions Go to Step 9 
6
  1. Monitor the DMM while disconnecting all other devices connected to the 5-volt reference circuit, one at a time. Refer to Engine Controls Component Views .
  2. If the voltage changes when one of the devices are disconnected, replace the component. Refer to appropriate replacement procedure below:
Did you complete the replacement?
- Go to Step 11  Go to Step 7 
7 Test the 5-volt reference circuit for a short to ground or any sensor low reference circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
- Go to Step 11  Go to Step 10 
8 Test all the 5-volt reference circuits and the MAP sensor signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
- Go to Step 11  Go to Step 10 
9 Replace the TP sensor. Refer to Throttle Position (TP) Sensor Replacement .
Did you complete the replacement?
- Go to Step 11  -
10 Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement .
Did you complete the replacement?
- Go to Step 11  -
11
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running 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 12 
12 Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?
- Go to Diagnostic Trouble Code (DTC) List System OK