C15 – Service Brake Pedal Position (Switch 1) Circuit – Test

System Operation Description:

Use this procedure under the following situation:

Use this procedure to determine if the Service Brake Pedal Position (Switch 1) is preventing normal operation of cruise control, idle set speed, or PTO operation:

The following switch circuits can also prevent the correct operation of the cruise control, idle set speed or PTO operation:

• Service Brake Pedal Position (Switch 1)
• Service Brake Pedal Position (Switch 2)
• Neutral Switch
• Cruise Control Set/Resume Switch
• Cruise Control On/Off Switch
• PTO On/Off Switch

The switches are described in the respective circuit tests in Troubleshooting.
All of the following customer programmable parameters can affect cruise control, idle set speed, and PTO operation:

• “Low Cruise Control Speed Set Limit”
• “High Cruise Control Speed Set Limit”

• “Idle Vehicle Speed Limit”
• “Cruise/Idle/PTO Switch Configuration”
• “Idle/PTO Bump rpm”
• “Idle/PTO rpm Ramp Rate”
• “PTO Vehicle Speed Limit”

The vehicle speed calibration can also affect the cruise control, the idle set speed, and the PTO if the vehicle speed calibration is incorrectly programmed. Refer to Troubleshooting, “Customer Specified Parameters”.

Service Brake Pedal Position (Switch 1)

The switch for the Service Brake Pedal Position (Switch 1) is normally closed when the respective pedal is released. Depressing the brake pedal should open the individual circuit. This switch is OEM supplied. The Service Brake Pedal Position (Switch 1) is typically a pressure switch.

Kick out Switches

The service brake pedal position switches, the neutral switch and the clutch switch are used in the cruise control mode, the PTO mode and the Idle mode in order to discontinue the cruise operation, the PTO operation, or the idle operation. The capability to override the idle shutdown timer is determined by the “Allow Idle Shutdown Override” parameter setting. The “Allow Idle Shutdown Override” is a customer parameter.

Usage of Transmission Style Switches

The “Transmission Style” parameter determines the switches that will be used. The following switches can be used with being dependent on the parameter setting:

• Clutch Pedal Position
• Neutral
• Service Brake Pedal Position (Switch 1)
• Service Brake Pedal Position (Switch 2)

Refer to Table 152 for additional information.

Test Step 1. Check the Status for the “Service Brake Pedal Position Switch #1”

A. Connect the electronic service tool to the data link connector.
B. Turn the key switch to the ON position.

C. Access the status for the “Service Brake Pedal Position Switch #1” on the electronic service tool.
D. While the status for the “Service Brake Pedal Position Switch #1” is monitored, depress the brake and release the brake.

Expected Result:
The status for the “Service Brake Pedal Position Switch #1” is “Off” when the brake is released. The status for the “Service Brake Pedal Position Switch #1” is “On” when the brake is depressed.

Results:
• OK – The service brake pedal position (Switch 1) is working correctly. STOP.
• Not OK – The service brake pedal position (Switch 1) is not working correctly. Proceed to Test Step 2.

Test Step 2. Determine the Configuration of the Switch

A. Determine if the wiring for the service brake pedal position (Switch 1) is wired directly to the ECM or through the J1939 data link.

B. Verify that the “Service Brake Pedal Position Switch #1” parameter is programmed to reflect the proper wiring.

Expected Result:
The service brake pedal position (Switch 1) is wired directly to the ECM.

Results:
• OK – The service brake pedal position (Switch 1) is wired directly to the ECM.

Repair: Verify that the “Service Brake Pedal Position Switch #1” parameter is programmed to “J1/P1:45”.

Proceed to Test Step 3.

• Not OK – The service brake pedal position
(Switch 1) is wired through the J1939 data link.

Repair: Verify that the “Service Brake Pedal Position Switch #1” parameter is programmed to “J1939 – Body Controller”, “J1939 – Cab Controller”, or “J1939 – Instrument Cluster”.
Refer to Troubleshooting, “Powertrain Data Link Circuit – Test”.

STOP.

Test Step 3. Inspect Electrical Connectors And Wiring

A. Thoroughly inspect the J1/P1 ECM connector, the firewall bulkhead connector and the terminals
for the following switches in the connectors:
• J1/P1:5 (AP Sensor/Switch Sensor Common)
• J1/P1:45 (Service Brake Pedal Position (Switch 1))
Refer to Troubleshooting, “Electrical Connectors – Inspect” for details.

B. Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the switches.
Refer to Illustration 171.

C. Check the ECM connector (allen head screw) for the proper torque of 6.0 N·m (55 lb in).

D. Check the harness and wiring for abrasion and pinch points from the sensor to the ECM.

Expected Result:
All connectors, pins, and sockets should be completely coupled and/or inserted and the harness and wiring should be free of corrosion, abrasion, or pinch points.

Results:
• OK – Proceed to Test Step 4.
• Not OK

Repair: Perform the following 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.

STOP.

Test Step 4. Check the Switch Circuit at the ECM

A. Turn the key switch to the OFF position.

B. Fabricate a jumper wire 100 mm (4 inch) long.
Crimp a Deutsch pin to both ends of the wires.

C. Connect a 140-2266 Cable (Seventy-Pin Breakout) between the J1 and P1 ECM connectors.

D. Install the jumper into terminal 45 (Service Brake Pedal Position Switch) of the breakout T. Connect the other end of the jumper to terminal 5 (AP Sensor/Switch Sensor Common) of the breakout T.

E. Turn the key switch to the ON position.

F. Access the status for the “Service Brake Pedal Position Switch #1”.

G. While the status for the “Service Brake Pedal Position Switch #1” is monitored, remove the jumper from terminal 5 and insert the jumper into terminal 5 (AP Sensor/Switch Sensor Common).

Expected Result:
The status for the “Service Brake Pedal Position
Switch #1” is “Off” when the jumper wire is removed.
The status for the “Service Brake Pedal Position
Switch #1” is “On” when the jumper wire is installed.

Results:
• OK – The ECM is functioning properly.
Repair: Remove the breakout T and reconnect the J1 and P1 ECM connectors.
Proceed to Test Step 5.

• Not OK – The ECM is not functioning properly.

Repair: Perform the following repair:
1. Temporarily connect a test ECM.
2. Remove the breakout T and reconnect the J1 and P1 ECM connectors.
3. If the problem is resolved with the test ECM, reconnect the suspect ECM.
4. If the problem returns with the suspect ECM, replace the ECM.
5. Verify that the repair eliminates the problem.

STOP.

Test Step 5. Insert a Jumper at the Service Brake Pedal Position (Switch 1)

A. Turn the key switch to the OFF position.

B. Find the switch for the Service Brake Pedal Position (Switch 1) in the vehicle.

C. Disconnect the wires from the switch terminals.

D. Turn the key switch to the ON position.

E. Access the status for the “Service Brake Pedal Position Switch #1”.

F. While the status for the “Service Brake Pedal Position Switch #1” is monitored, connect the wires for the service brake pedal position (Switch 1) and disconnect the wires for the service brake pedal position (Switch 1).

Expected Result:
The status for the “Service Brake Pedal Position Switch #1” is “Off” when the wires are disconnected.
The status for the “Service Brake Pedal Position Switch #1” is “On” when the wires are connected.

Results:
• OK

Repair: Replace the faulty switch.

Verify that the repair eliminates the problem.

STOP.

• Not OK – There is a problem in the harness between the switch and the ECM. Proceed to Test Step 6.

Test Step 6. Insert a Jumper at the Bulkhead Connector

A. Turn the key switch to the OFF position.

B. Fabricate a jumper wire 100 mm (4 inch) long.
Crimp a Deutsch pin to each end of the wire.

C. Locate the terminal for the “Service Brake Pedal Position (Switch 1)” and the “AP Sensor/Switch Sensor Common” on the engine side of the bulkhead connector.

D. Insert the jumper wire between the two terminals in the engine side of the bulkhead connector.

E. Turn the key switch to the ON position.

F. Access the status for the “Service Brake Pedal Position Switch #1”.

G. While the status for the “Service Brake Pedal Position Switch #1” is monitored, remove the jumper from one of the terminals and insert the jumper wire into the terminal.

Expected Result:
The status for the “Service Brake Pedal Position Switch #1” is “Off” when the jumper wire is removed.
The status for the “Service Brake Pedal Position Switch #1” is “On” when the jumper wire is installed.

Results:
• OK – The problem is in the vehicle wiring
between the bulkhead connector and the switch.

Repair: Inspect the vehicle wiring and repair the vehicle wiring, as required. If the problem still exists with the wiring, send the vehicle to the OEM dealer.

STOP.

• Not OK – The problem is in the vehicle wiring between the bulkhead connector and the ECM.

Repair: Inspect the vehicle wiring and repair the vehicle wiring, as required. If the problem still exists with the wiring, send the vehicle to the OEM dealer.

STOP.

 

 

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