MLP Tester Instruction
MLP TESTER INSTRUCTIONSThe transaxle tester allows the technician to operate the electrical portion of the TR switch. The MLP tester usage is divided into five steps.
1. Preliminary testing and diagnosis.
2. Installing the transaxle tester.
3. Testing the TR switch.
4. Testing the Park/Neutral and backup circuits.
5. Removing the transaxle tester and clearing DTCs.
Preliminary Testing and Diagnosis
Before any diagnostic testing is done on a vehicle, some preliminary checks must be performed, as outlined below. Be sure to write down your findings, especially any DTCs found, for future reference.
- Check ATF level and condition.
- Check for add-on items (phones, computers, OB radio etc).
- Visually inspect wiring harness and connector.
- Check for vehicle modifications.
- Verify that the shift linkage is properly adjusted in "OVERDRIVE".
- Verify that TR switch is properly adjusted in "NEUTRAL".
- Verify customer concern.
- Upshift, Downshift, Coasting, Engagement, Noise/Vibration
- Vehicle must be at normal operating temperature.
- Perform vehicle On-Board Diagnostic Test.
- Record all DTCs.
- Repair all non-transaxle DTCs.
Installing the Transaxle Tester (Set Up Procedures)
Installing the transaxle tester at the TR switch connector allows the separation of the vehicle electronics from the TR switch electronics.
NOTE: During tester usage, additional DTCs may be set. Therefore, it is important that all DTCs are erased after repairs have been made. To verify the elimination of all DTCs, rerun the On-Board Diagnostic Test.
CAUTION: Do not attempt to pry off connectors with a screwdriver. This will damage the connector and could result in a transaxle concern.
1. Disconnect the emission harness at transaxle TR switch connector.
MLP Attached To TR Switch:
NOTE: For in vehicle testing, use the SST.
CAUTION: Route all cables away from heat sources.
2. Set the Bench/Drive switch to "DRIVE" mode. Install the SST onto the tester. Connect the interface cable (cable I.D. "D") to the transaxle tester and then to the TR switch connector.
MLP SENSOR TEST POSITION:
3. Turn the test select switch to the "MLP SENSOR TEST" position.
4. Plug the transaxle tester power supply plug into the cigarette lighter receptacle.
MLP Tester - SST:
At this time, all LED's should illuminate for a short period and then turn off. This is the tester internal circuit check.
Testing the TR Switch
Static testing procedures allow for shop testing of the transaxle in the vehicle or on the bench. Completion of these tests prove out the TR switch electronically.
MLP SENSOR TEST POSITION:
CAUTION: For resistance checks, be sure that the tester select switch is set to the "MLP SENSOR TEST" position or damage to the ohmmeter may result.
Resistance/Continuity Tests
- Using a digital volt-ohmmeter and the transaxle tester, perform the pinpoint test "D" based on the DTCs which were displayed.
- Perform repairs as indicated by the pinpoint test. Always retest and road test the vehicle after a repair.
TR Switch resistance tests
TR Switch - Set the ohmmeter to the 1,000 Ohm range.
- Connect the positive lead of the ohmmeter to the MLP jack.
- Connect the negative lead of the ohmmeter to the SIGRTN jack.
- Move the selector lever into each range position.
- Record the resistance at each position.
TR Switch Resistance Chart:
- Refer to the chart for values,
- If out of range, refer to the DTC test P0707.
Park/Neutral Backup Light And Optional Circuit Voltage Tests
NOTE: LED will turn "RED" when the circuit is closed and turn "OFF" when the circuit is open.
MLP Tester Switch Position:
1. Set the tester select switch to the "MLP SENSOR TEST" position.
2. Press and hold each button while moving the selector lever through each range position.
MLP LED Function:
3. Monitor each "LED".
4. The status "LED" should indicate "RED" only in the indicated position. Refer to the overlay.
5. If the LED does not indicate "RED" in the desired position, or indicated "RED" in another position, first verify the TR switch alignment and then retest. If the switch fails, then replace.
Removing The Transaxle Tester And Clearing DTC
CAUTION: Do not attempt to pry off connectors with a screwdriver. This will damage the connector and could result in a transaxle concern.
MLP Hookup:
1. Disconnect the transaxle tester from the TR switch connector.
2. Reinstall the emission harness. Verify the connection by pulling up on the harness.
MLP Tester:
3. Disconnect the transaxle tester power lead from vehicle.
4. Erase all DTCs. (Unlatch the center button of the star tester while the codes are being displayed on a KOEO on-board diagnostic test)
5. Return to the on-board diagnostic test.
6. Verify that the customer concern has been eliminated.