0115767 JOHNSON DECAL SET, Ev., 2.3

Illustration 1 g00734314
Schematic
Test Step 1. Inspect Electrical Connectors and Wiring
Turn the keyswitch to the OFF/RESET position.
Thoroughly inspect the right hand brake pedal switch, the ECM connector J1/P1, the machine connector J3/P3, and the associated wiring. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details. Expected Result:All connectors, pins, and sockets should be completely inserted and coupled. The harness and wiring should be free of corrosion, abrasion, and pinch points.Results:
OK - Proceed to Test Step 2.
Not OK - Repair: Repair the circuit.Verify that the repair eliminates the problem.STOPTest Step 2. Check the Status on ET
Connect ET to the service tool connector.
Turn the keyswitch to the ON position.
Observe the status for "Brake Pedal" on ET while you operate the right brake pedal. Expected Result:The status for the right hand brake pedal switch should read "Depressed" when the brake pedal is depressed. The status for the right hand brake pedal switch should read "Released" when the brake pedal is released.Results:
OK - The right hand brake pedal switch is operating properly at this time.Repair: Refer to Troubleshooting, "Electrical Connectors - Inspect" if the problem is intermittent.STOP
Not OK - Proceed to Test Step 3.Test Step 3. Short the Wires at the Right Brake SwitchNote: Record the switch wiring for correct reconnection before removing wires.
Turn the keyswitch to the OFF position.
Disconnect the wires from the right hand brake switch.
At the switch, short wires F721-GY(Grey) and 998-BR(Brown) together. Wire F722-OR(Orange) should remain open.
Turn the keyswitch to the ON position, and observe the status for "Brake Pedal" on ET.
Turn the keyswitch to the OFF position. Disconnect the F721-GY(Grey)wire and the 998-BR(Brown)wire, and short the F722-OR(Orange) wire and the 998-BR(Brown) wire together. Wire F721-GY(Grey) should remain open.
Turn the keyswitch to ON position, and observe the status for "Brake Pedal" on ET.
Disconnect the shorted wires, and leave the wires disconnected at the switch. Expected Result:The "Brake Pedal" status should read "Released" when F721-GY(Grey) and 998-BR(Brown) are shorted together. The status should read "Depressed" when F722-OR(Orange) and 998-BR(Brown) are shorted together.Results:
OK - The ECM and the wiring harness are functioning properly. Replace the right hand brake switch. Verify that the repair eliminates the problem.STOP
Not OK - Proceed to Test Step 3.Test Step 4. Check for a Short Circuit in the Wiring Harness
Illustration 2 g00759613
ECM connector P1
Disconnect ECM connector J1/P1, and ensure that the wires at the right hand brake pedal switch are disconnected.
Measure the following resistances:
P1:13 (RH Service Brake Switch (NO)) and P1:29 (Digital Return)
P1:19 (RH Service Brake Switch (NC)) and P1:29 (Digital Return)
P1:13 (RH Service Brake Switch (NO)) and P1:19 (RH Service Brake Switch (NC))
P1:19 (RH Service Brake Switch (NC)) and the engine ground
P1:13 (RH Service Brake Switch (NC)) and the engine groundExpected Result:The resistance should be greater than 20,000 Ohms for each measurement.Results:
OK - There are no shorts in the harness. Proceed to Test Step 5.
Not OK - There is a short circuit in the harness or connectors.Repair: Repair the circuit.Verify that the repair eliminates the problem.STOPTest Step 5. Check the Resistance through the Harness
Ensure that the ECM connector J1/P1 is disconnected, and ensure that the wires at the right hand brake pedal switch are disconnected.
Short the F722-OR(Orange) wire and the 998-BR(Brown) wire together at the right hand brake pedal switch.
Measure the resistance between P1:13 (RH Service Brake Pedal Switch (NO)) and P1:29 (Digital Return).
Disconnect the shorted wires, and short the F721-GY(Grey) wire and the 998-BR(Brown) wire together at the switch.
Measure the resistance between P1:19 (RH Service Brake Pedal Switch (NC)) and P1:29 (Digital Return).
Disconnect the shorted wires. Expected Result:The resistance should be less than 10 Ohms for each measurement.Results:
OK - The harness is good. Proceed to Test Step 6.
Not OK - There is an open circuit or excessive resistance in the harness or the connectors.Repair: Repair the circuit.Verify that the repair eliminates the problem.STOPTest Step 6. Short the Switch Inputs at the ECM
Illustration 3 g00734605
ECM connector P1 (wire insertion side)
Turn the keyswitch to the OFF position.
Remove the following wires from the ECM connector P1:
P1:13 (RH Service Brake Pedal Switch (NO))
P1:19 (RH Service Brake Pedal Switch (NC))
P1:29 (Digital Return)
Fabricate a jumper wire out of 18 AWG insulated wire with Deutsch socket terminals on each end.
Insert one end of the jumper wire into P1:19 (RH Service Brake Pedal Switch (NC)) on the ECM connector P1 and insert the other end into P1:29 (Digital Return) on the ECM connector P1.
Reconnect the ECM connector J1/P1.
Turn the keyswitch to the ON position. Note: Additional diagnostic codes will be generated because P1:29 (Digital Return) will no longer be connected to other sensors and switches. Clear the additional diagnostic codes upon completing this test.
Observe the status for "Brake Pedal" on ET.
Turn the keyswitch to the OFF position.
Disconnect the ECM connector J1/P1 and remove the end of the jumper wire from P1:19 (RH Service Brake Pedal Switch (NC)). Leave the other end of the jumper wire in P1:29 (Digital Return).
Insert the loose end of the jumper wire into P1:13 (RH Service Brake Pedal Switch (NO)) on the ECM connector P1.
Reconnect the ECM connector J1/P1.
Turn the keyswitch to the ON position.
Observe the status for "Brake Pedal" on ET.
Turn the keyswitch to the OFF position, and remove the jumper wire from the ECM connector P1. Reconnect the following wires to the ECM connector P1:
P1:13 (RH Service Brake Pedal Switch (NO))
P1:19 (RH Service Brake Pedal Switch (NC))
P1:29 (Digital Return)Expected Result:The status for "Brake Pedal" should read "Released" when one end of the jumper wire is inserted into P1:19 (RH Service Brake Pedal Switch (NC)) and the other end is inserted into P1:29 (Digital Return). The status should read "Depressed" when one end of the jumper wire is inserted into P1:13 (RH Service Brake Pedal Switch (NO)) and the other end is inserted into P1:29 (Digital Return).Results:
OK - The ECM properly reads the switch inputs at the ECM connector P1 but not at the switch.Repair: The wiring harness is faulty. Repair the wiring harness. Verify that the repair eliminates the problem.STOP
Not OK - Correct switch inputs appear at the ECM connector P1 but the ECM is not reading the inputs properly.Repair: