5033690 JOHNSON SEAL

Illustration 1 g01254251
Schematic of the switch circuit for the PTO engine RPM set speed "Input A" and "Input B"
Test Step 1. Check the Status of the "PTO Engine RPM Set Speed Input A" and "PTO Engine RPM Set Speed Input B"
Connect Caterpillar Electronic Technician (ET) to the service tool connector.
Turn the keyswitch to the ON position.
Monitor the status for the "PTO Engine RPM Set Speed Input A" and the "PTO Engine RPM Set Speed Input B" while the appropriate switch is toggled to the ON position and the OFF position. The correct status for the "PTO Engine RPM Set Speed Input A" and the "PTO Engine RPM Set Speed Input B" is "On" when the switch is in the ON position. The correct status for the "PTO Engine RPM Set Speed Input A" and the "PTO Engine RPM Set Speed Input B" is "Off" when the switch is in the OFF position.Note: If the status for the "PTO Engine RPM Set Speed Input A" or the "PTO Engine RPM Set Speed Input B" indicates "Not Installed", then the appropriate parameter has not been programmed.Expected Result:Cat ET is reporting the correct status for each of the switches.Results:
OK - Cat ET is reporting the correct status for each of the switches.Repair: The circuits for the "PTO Engine RPM Set Speed Input A" and the "PTO Engine RPM Set Speed Input B" appear to be operating correctly at this time. There may be an intermittent electrical problem in the harness or in a connector. If an intermittent problem is suspected, refer to Troubleshooting, "Electrical Connectors - Inspect" for information that is related to troubleshooting intermittent electrical problems.STOP
Not OK - Cat ET is not reporting the correct status for one of the switches. The ECM is not reading the change in switch status. Proceed to Test Step 2.Test Step 2. Determine the Configuration of the "PTO Engine RPM Set Speed Input A" and the "PTO Engine RPM Set Speed Input B"
Determine if the ECM inputs for the "PTO Engine RPM Set Speed Input A" and the "PTO Engine RPM Set Speed Input B" are wired correctly.
Verify that the parameter for the suspect switch is programmed to reflect the current wiring for the circuit. Expected Result:The wiring for the suspect switch is correct.Results:
OK - The wiring for the suspect switch is correct. Proceed to Test Step 3.
Not OK - The wiring for the circuit of the suspect switch is not wired to the correct ECM input.Repair: Correct the wiring for the switch circuit. Verify that the repair eliminates the problem.STOPTest Step 3. Check the Electrical Connectors and the Wiring
Turn the keyswitch to the OFF position.
Illustration 2 g01186024
Location of the J1/P1 ECM connectors (typical left side engine view)
Thoroughly inspect the J1/P1 ECM connectors and the firewall bulkhead connectors. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Illustration 3 g01254406
Terminal locations at the P1 ECM connector for the PTO engine RPM set speed "Input A" and "Input B"
(P1-5) AP sensor/switch sensor return
(P1-6) Output No. 6
(P1-46) Output No. 7
(P1-58) Output No. 2
(P1-60) Output No. 3
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the suspect switch circuit.
Check the allen head screw for each of the ECM connectors for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.
Check the harness and the wiring for abrasion and for pinch points from the battery to the ECM. Expected Result:All connectors, pins and sockets are completely coupled and/or inserted and the harness and wiring are free of corrosion, of abrasion and of pinch points.Results:
OK - The harness and connectors appear to be OK. Proceed to Test Step 4.
Not OK - There is a problem with the connectors and/or wiring.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled. Verify that the repair eliminates the problem.STOPTest Step 4. Create a Short Circuit at the Switch
Fabricate a jumper wire that is long enough to create a short circuit across the terminals at the harness connector for the suspect switch.
Disconnect the switch from the harness.
Install the jumper wire across the two switch terminals at the harness connector for the switch.
Turn the keyswitch to the ON position.
Use Cat ET to monitor the status of the "PTO Engine RPM Set Speed Input A" or the "PTO Engine RPM Set Speed Input B". While the status for the "PTO Engine RPM Set Speed Input A" or the "PTO Engine RPM Se