PLATE-WARNING 6P4350 - Caterpillar

Illustration 8 g00643436
Jumper wire locations for breakout T
Turn the ignition key switch to the OFF position.
Fabricate two jumper wires 100 mm (4 inch) long. Crimp a Deutsch pin to both ends of the wires.
Disconnect vehicle harness connector P1 from the ECM.
Connect a breakout T to ECM connector J1 and connect P1 to the breakout T.
Install one jumper into the breakout T in order to connect terminal 36 (speedometer positive) to terminal 32 (vehicle speed in positive). Install the other jumper into the breakout T in order to connect terminal 37 (speedometer negative) to terminal 33 (vehicle speed in negative).Refer to Illustration 8.
Turn the ignition key switch to the ON position.
Connect ET to the cab data link connector.
Access the "55 mph VSP/Speedometer Test" by Accessing the following display screens in order:
"Diagnostics"
"Diagnostic Tests"
"Special Test menu"
Activate the test and observe the vehicle speed on the vehicle speed status screen.Expected Result:ET indicates a constant vehicle speed between 80 to 96 km/h (50 to 60 mph) when the jumper wires from the speedometer circuit are connected.Results:
OK - The ECM is operating correctly. The source of the problem is either the wiring or the source of the problem is the vehicle speed sensor.Repair: Perform the following repair:If the sensor is damaged, replace the damaged sensor or send the vehicle to the OEM dealer for repairs.Verify that any repair eliminates the problem.STOP
Not OK - Recheck the connections of the jumper wires. Leave the jumper wires installed in the breakout T. Disconnect the breakout T. Proceed to Test Step 8.Test Step 8. Test the ECM Vehicle Speed Inputs When the Test ECM is Installed.
Connect a test ECM and reconnect the breakout T.
Install one jumper into the breakout T in order to connect terminal 36 (speedometer positive) to terminal 32 (vehicle speed in positive). Install the other jumper into the breakout T in order to connect terminal 37 (speedometer negative) to terminal 33 (vehicle speed in negative).Refer to Illustration 8.
Turn the ignition key switch to the ON position.
Connect ET to the cab data link connector.
Access the "55 mph VSP/Speedometer Test" by Accessing the following display screens in order:
"Diagnostics"
"Diagnostic Tests"
"Special Test menu"
Activate the test and observe the vehicle speed on the vehicle speed status screen.Expected Result:ET indicates a constant vehicle speed between 80 to 96 km/h (50 to 60 mph) when the jumper wires from the speedometer circuit are connected.Results:
OK - Repair: Perform the following repair:Reconnect the suspect ECM. If the problem returns with the suspect ECM, replace the ECM.STOP
Not OK - Recheck the connectors. Continue troubleshooting until original condition is resolved.STOPTest Step 9. Verify Correct Programming for the "J1939 Vehicle Speed Calibration" Parameter
Connect ET to the cab data link connector.
Access the list of "Configuration Parameters" on the service tool and verify that the "Vehicle Speed Input" parameter is programmed to the "J1939 Trans" option.
Verify that the "Powertrain Datalink" parameter is programmed to "J1939".
Verify that the correct value is used for the "Vehicle Speed Cal (J1939-Trans)" parameter. Refer to Troubleshooting, "Vehicle Speed Circuit - Calibrate" for details.
Verify that the