Test Description
The numbers below refer to the step numbers on the diagnostic table.
- This step determines if the Scan Tool is receiving power through the DLC connector.
- The MIL should illuminate whenever the ignition is ON and the engine is not running.
- This step determines if the PCM is transmitting Class 2 serial data to the DLC and that the Class 2 data circuit is not open or shorted.
- This step determines if a DTC is current or stored in history.
The numbers below refer to the step numbers in the diagnostic table.
- 6. This step checks the VSS sensor for a battery positive supply.
- 7. This step checks the VSS sensor for a ground supply.
- 8. This step checks for a shorted to ground speedometer vehicle speed input circuit.
- 9. This step checks the VSS for an output signal.
- 10. This step checks the PCM vehicle speed input circuit for continuity to the speedometer.
- 11. This step checks the speedometer for an output signal. Each 1 Hz of frequency is approximately equal to one mile per hour.
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| Bold SPECIFICATIONS | ||||
| 1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | Go to Step 2 | Go to DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS in Engine Controls | |
| 2 | Raise the drive wheels. Support the lower control arms so that the drive axles are in a horizontal position. Start and idle the engine. Observe the vehicle speed parameter on the scan tool. Allow the engine to idle in gear with the drive wheels rotating. Does the scan tool parameter indicate a vehicle speed? | Go to Step 3 | Go to Step 4 | |
| 3 | Using the scan tool, store the DTC Freeze Frame information. Perform the scan tool Clear DTC Information function. Place the vehicle into Check mode using the scan tool. Operate the vehicle within the Freeze Frame conditions. Does DTC P0500 set? | Go to Step 4 | Go to Diagnostic Aids | |
| 4 | Raise the drive wheels. Support the lower control arms so that the drive axles are in a horizontal position. Start and idle the engine. Observe the speedometer. Allow the engine to idle in gear with the drive wheels rotating. Does the speedometer indicate a vehicle speed? | Go to Step 10 | Go to Step 5 | |
| 5 | Do all other instrument cluster assembly functions operate normally? | Go to Step 6 | Go to DIAGNOSTIC STARTING POINT - INSTRUMENT PANEL, GAGES AND CONSOLE in Instrument Panel, Gages, and Console | |
| 6 | Turn OFF the ignition. Disconnect the VSS electrical connector. Turn ON the ignition, with the engine OFF. Probe the VSS connector terminal 1 on the harness side with a test lamp connected to ground. Does the test lamp illuminate? | Go to Step 7 | Go to Step 12 | |
| 7 | Probe the VSS connector terminal 2 on the harness side with a test lamp connected to B+. Does the test lamp illuminate? | Go to Step 8 | Go to Step 13 | |
| 8 | Probe the VSS connector terminal 3 on the harness side with a test lamp connected to B+. Does the test lamp illuminate? | Go to Step 14 | Go to Step 9 | |
| 9 | Reconnect the VSS connector. Disconnect the instrument panel cluster (IPC) connector C2. Set-up the digital multimeter (DMM) to measure the DC frequency (push the Hz button) on the speedometer vehicle speed input circuit terminal 10. Start and idle the engine. Allow the engine to idle in gear with the drive wheels rotating. Does the DMM indicate a frequency? | Go to Step 18 | Go to Step 15 | |
| 10 | Turn OFF the ignition. Disconnect PCM electrical connector C3, containing the vehicle speed input terminal. Turn ON the ignition, with the engine OFF. Probe the vehicle speed input circuit terminal on the harness side with the DMM connected to ground. Measure the DC voltage on the vehicle speed input circuit. Is the voltage within the specified value? | 9-12 V | Go to Step 11 | Go to Step 16 |
| 11 | Set-up the DMM to measure the DC frequency - push the Hz button on the PCM vehicle speed input circuit. Start and idle the engine. Allow the engine to idle in gear with the drive wheels rotating. Does the DMM indicate a frequency? | Go to Step 20 | Go to Step 17 | |
| 12 | Repair the cause of no power to the VSS connector. Refer to WIRING REPAIRS in Wiring Systems. Is the action complete? | Go to Step 21 | ||
| 13 | Repair the cause of no ground to the VSS connector. Refer to WIRING REPAIRS in Wiring Systems. Is the action complete? | Go to Step 21 | ||
| 14 | Check the speedometer vehicle speed input circuit for a short to ground. Repair as necessary. Refer to WIRING REPAIRS in Wiring Systems. Was a repair necessary? | Go to Step 21 | Go to Step 18 | |
| 15 | Check the speedometer vehicle speed input circuit for an open. Repair as necessary. Refer to WIRING REPAIRS in Wiring Systems. Was a repair necessary? | Go to Step 21 | Go to Step 19 | |
| 16 | Check the PCM vehicle speed input circuit for a short to ground or open. If equipped, ensure that the cruise control module is not shorted internally. 2. Repair as necessary. Refer to WIRING REPAIRS in Wiring Systems. Was a repair necessary? | Go to Step 21 | Go to Step 18 | |
| 17 | Check the PCM vehicle speed input circuit for a short to battery positive. Repair as necessary. Refer to WIRING REPAIRS in Wiring Systems. Was a repair necessary? | Go to Step 21 | Go to Step 18 | |
| 18 | Replace the speedometer. Refer to INSTRUMENT PANEL CLUSTER (IPC) REPLACEMENT in Instrument Panel, Gages, and Console. Is the replacement complete? | Go to Step 21 | ||
| 19 | Replace the VSS. Refer to VEHICLE SPEED SENSOR (VSS) REPLACEMENT VEHICLE SPEED SENSOR (VSS) REPLACEMENT . Is the replacement complete? | Go to Step 21 | ||
| 20 | Replace the PCM. Refer to POWERTRAIN CONTROL MODULE (PCM) REPLACEMENT in Engine Controls. Is the replacement complete? | Go to Step 21 | ||
| 21 | Perform the scan tool Clear DTC Information function and road test the vehicle with the Freeze Frame conditions that set the DTC. Review the scan tool data and check for DTCs. The repair is complete if no DTCs are stored. Are any DTCs displayed on the scan tool? | Go to DIAGNOSTIC TROUBLE CODE (DTC) LIST/TYPE | System OK | |
DTC P0500 DIAGNOSIS PROCEDURE CHART
The numbers below refer to the step numbers on the diagnostic table.
- 1. The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
- 3. This step checks for proper shift points.
- 5. This step checks for a leaky shift solenoid #1.
- 6. This step checks for a stuck closed shift solenoid #1.
- 8. This step checks the condition of the valve body assembly.
- 9. This step checks for a faulty PCM.
The numbers below refer to the step numbers on the diagnostic table.
- The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
- This step inspects the shift solenoid internal coil resistance.
- This step inspects for a short to ground in the shift solenoid #1 control circuit.
- This step inspects for an open in the shift solenoid #1 control circuit.
- This step inspects the transaxle internal electrical harness for damage.
- This step inspects for a short to voltage in the shift solenoid #1 control circuit.
- This step inspects for a poor electrical connection that may have caused DTC to set.
- This step inspects for a faulty PCM.
The numbers below refer to the step numbers on the diagnostic table.
- 1. The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
- 3. This step checks for proper shift points.
- 5. This step checks for a leaky shift solenoid #2.
- 6. This step checks for a stuck closed shift solenoid #2.
- 8. This step checks the condition of the valve body assembly.
- 9. This step checks for a faulty PCM.
The numbers below refer to the step numbers on the diagnostic table.
- >The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
- This step inspects the internal coil resistance of the shift solenoid.
- This step inspects for a short to ground in BLU wire.
- This step inspects for an open in the BLU wire.
- This step inspects the condition of the transaxle internal electrical harness for damage.
- This step inspects for a short to voltage in the BLU wire.
- This step inspects for a poor electrical connection that may have caused the DTC to set.
- This step inspects for a faulty PCM.
The numbers below refer to the step numbers on the diagnostic table.
- 1. The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
- 4. This step checks for proper shift points.
- 5. This step checks for a stuck closed lock-up solenoid.
- 6. This step checks for a leaky lock-up solenoid.
- 7. This step checks the condition of the valve body assembly.
- 8. This step checks for a faulty PCM.
The numbers below refer to the step numbers on the diagnostic table.
- The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
- This step tests the shift solenoid for internal coil resistance.
- This step tests for a short to ground in the BLUNVHT wire.
- This step tests for a open in the BLUNVHT wire.
- This step tests the condition of the transaxle internal electrical harness for damage.
- This step tests for a short to voltage in the BLUNVHT wire.
- This step tests for a poor electrical connection that may have caused the DTC to set.
- This step inspects for a faulty PCM.7-1 16 Automatic Transmission - MU4 Transmission/Transaxle
The numbers below refer to the step numbers in the diagnostic table.
- 1. The OBD System Check prompts the technician to complete some basic checks and store the Freeze Frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
- 3. This step will determine if the fault is in the stop lamp switch.
- 4. This step will determine whether there is a short to voltage in the stop lamp circuit between the PCM and the stoplamp switch.
- 6. This step will determine whether there is a short to voltage within the PCM, or a short to voltage in the circuit between the PCM and the stop lamp switch.
The numbers below refer to the step numbers on the diagnostic table.
- 1. The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
- 5. This step checks for a faulty PCM.
- 6. This step checks for a faulty solenoid.
The numbers below refer to the step numbers on the diagnostic table.
- The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
- This step checks the L position signal circuit.
- This step checks the N and the P position signal circuit.
- This step checks the P position signal circuit.
- This step checks the R position signal circuit.
- This step checks for poor terminal contact at the PCM.
- This step checks for a faulty PCM.
- This step checks for a short to voltage in the L position.
- This step checks for a short to ground in the L position.
- This step checks for an open in the L position.
- This step checks for a short to voltage in the N and P positions.
- This step checks for a short to ground in N and P positions.
- This step checks for an open in N and P positions.
- This step checks for a short to voltage in the 2 position.
- This step checks for a short to ground in the 2 position.
- This step checks for an open in the 2 position.
- This step checks for a short to voltage in R position.
- This step checks for a short to ground in R position.
- This step checks for an open in R position.
The numbers below refer to the step numbers on the diagnostic table.
- The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.
- This step checks the O/D OFF indicator light by jumping the switch to ground.
- This step checks the ground circuit and the Overdrive switch.
- This step checks for an open LT GRN wire or an open indicator bulb.
Transmission General Description
The MU4 is a fully automatic front wheel drive electronically controlled transmission. The PCM controls shift points by means of two shift solenoids. A third solenoid controls the application of the Torque Converter Clutch. A gear driven oil pump supplies the oil pressure. The PCM regulates oil pressure by means of a pressure control solenoid valve.
You can operate the transmission in any one of the following seven modes
- P - Park position prevents the vehicle from rolling either forward or backward. For safety reasons, use the parking brake in addition to the park position.
- R - Reverse allows the vehicle to be operated in a rearward direction.
- N - Neutral allows the engine to be started and operated while driving the vehicle. If necessary, you may select this position in order to restart the engine with the vehicle moving.
- Overdrive - Overdrive is used for all normal driving conditions. Overdrive provides a fourth gear ratio which can be engaged or disengaged manually. Depress the accelerator in order to downshift for safe passing.
- D - Drive position is used for city traffic and hilly terrain. Drive provides three gear ranges and drive range prevents the transmission from operating in Overdrive. Depress the accelerator in order to downshift.
- 2 - Manual Second provides two gear ratios under most operating conditions. Manual Second provides acceleration and engine braking. Select this range at any vehicle speed, but the transmission will not downshift into Second gear until the vehicle speed drops below approximately 97 km/h (60 mph)
- 1 - Manual Lo provides maximum engine braking. You may also select this range at any vehicle speed, but the transmission will not downshift into First gear until the vehicle speed drops below approximately 46 km/h (28 mph).
