LEMON Manuals: Even more car manuals for everyone
Home >> Pontiac >> 2004 >> Sunfire Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 91 (Automatic Transaxle - 4T40-E/4T45-E Diagnosis (DTC P0218 To P0748 - 2.2L)) >> Diagnostic Information and Procedures >> DTC P0502 (3.4L) >> Test Description

Test Description

WARNING: This page is about a different car, the 2004 Pontiac Grand Am and 2004 Oldsmobile Alero. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers on the diagnostic table.

  1. 3:  This step tests the ability of the OSS to produce an AC voltage. This step also verifies the integrity of the wiring to the PCM.
  2. 4:  This step tests the OSS circuit for correct resistance.
DTC P0502 (3.4L)

Step Action Value(s) Yes No
1 Did you perform the Diagnostic System Check - Engine Controls? - Go to Step 2  Go to Diagnostic System Check - Engine Controls in Engine Controls -3.4L
2
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
    3. IMPORTANT: Before clearing the DTC, use the scan tool in order to record the Freeze Frame and Failure Records. Using the Clear Info function erases the Freeze Frame and Failure Records from the PCM.
  3. Record the DTC Freeze Frame and Failure Records.
  4. Clear the DTC.
    5. NOTE: Refer to Drive Axles Notice in Cautions and Notices.
  5. Raise and support the drive wheels.
  6. Start and idle the engine.
  7. Place the transmission in DRIVE.
  8. Select Transmission OSS on the scan tool.
With the drive wheels rotating, does Transmission OSS increase when the wheel speed increases?		 - Go to Intermittent Conditions in Engine Controls - 3.4L Go to Step 3 
3 
  1. Turn OFF the ignition.
  2. Disconnect the PCM connector C1.
  3. Using the J 35616  GM-approved terminal test kit, connect the DMM between the OSS high signal circuit and the OSS low signal circuit at the PCM connector.
  4. Select AC volts on the DMM.
  5. Turn ON the ignition, with the engine OFF.
  6. Rotate the right front drive wheel by hand.
  7. Observe the DMM display.
Can a voltage greater than the specified value be obtained?		 0.5 V AC Go to Step 14  Go to Step 4 
4 
  1. Leave the DMM test leads connected.
  2. Measure circuit resistance.
Is the circuit resistance within the specified range?		 1,530-1,870 ohm Go to Step 8  Go to Step 5 
5 Is the circuit resistance greater than the specified value? 1,870 ohm Go to Step 11  Go to Step 6 
6
  1. Leave the DMM test leads connected.
  2. Disconnect the OSS connector at the transmission.
Is the circuit resistance less than the specified value?		 1,530 ohm Go to Step 7  Go to Step 13 
7 Test the high signal circuit and the low signal circuit of the OSS for being shorted together.
Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 15  -
8 Test the high signal circuit of the OSS for a short to ground.
Refer to Testing for Short to Ground and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 15  Go to Step 9 
9
  1. Connect PCM connector C1.
  2. Select DC volts on the DMM.
  3. Using the J 35616  , connect the DMM test leads to the OSS high signal circuit and the OSS low signal circuit of the OSS connector.
  4. Turn ON the ignition, with the engine OFF.
Does the DMM display system voltage?		 - Go to Step 10  Go to Step 12 
10 Test the high signal circuit of the OSS for a short to voltage.
Refer to Testing for a Short to Voltage and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?		 - Go to Step 15  -
11
  1. Test the high signal circuit of the OSS for an open.
  2. Test the low signal circuit of the OSS for an open.
Refer to Testing for Continuity and Wiring Repairs in Wiring Systems.Did you find and correct a condition?		 - Go to Step 15  Go to Step 13 
12
  1. Remove the OSS.

    Refer to Vehicle Speed Sensor (VSS) Replacement .

  2. Inspect the OSS and the transmission for the following conditions:
    • Incorrect OSS
    • OSS damage
    • Excessive OSS to speed sensor rotor gap
    • Incorrect speed sensor rotor alignment
    • Speed sensor rotor damage
  3. Repair any of the above conditions as necessary.
Refer to Final Drive Assembly Disassemble or Output Shaft Speed Sensor Installation in Transmission Unit Repair article.Did you complete the repair?		 - Go to Step 15  -
13 Replace the OSS.
Refer to Vehicle Speed Sensor (VSS) Replacement .
Did you complete the replacement?		 - Go to Step 15  -
14 Replace the PCM.
Refer to Powertrain Control Module (PCM) Replacement in Engine Controls - 3.4L.
Did you complete the replacement?		 - Go to Step 15  -
15 Perform the following procedure in order to verify the repair:
  1. Select DTC.
  2. Select Clear Info.
  3. Drive the vehicle in D4.
  4. The transmission output speed must be greater than 250 RPM for 2 seconds.
  5. Select Specific DTC.
  6. Enter DTC P0502.

Has the test run and passed?		 - Go to Step 16  Go to Step 2 
16 With the scan tool, observe the stored information, capture info and DTC info.
Does the scan tool display any DTCs that you have not diagnosed?		 - Go to Diagnostic Trouble Code (DTC) List in Engine Controls - 3.4L System OK
scientia non olet · About LEMON Manuals