Test Step 3. Check the Switch Circuit at the ECM

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TM 9-2320-312-24-2

Troubleshooting Section

C. Operate the switch in the ON and OFF positions.

D. View the status for parameter "Input # 5" on ET.

Note: For "OCT01" software, view the status for

"Ignore Brake/Clutch Switch".

E. If the status for parameter "Input # 5" indicates

"None", then the "Input # 5" parameter has not

been programmed.

Expected Result:

The status screen should indicate "On" if the switch

is turned ON. The status screen should indicate

"Off" if the switch is turned OFF.

Results:

Yes The switch is operating normally. Continue

troubleshooting if the original condition is not

resolved. STOP.

No The ECM is not reading the change in

switch status. Proceed to Test Step 3.

Test Step 3. Check the Switch Circuit at

the ECM.

g00682301

Illustration 124

Connector for breakout T

F. Turn the ignition key switch to the ON position.

A. Turn the ignition key switch to the OFF position.

G. Alternately remove the jumper wire and insert

B. Install a breakout T to the ECM vehicle harness

the jumper wire at terminal 18 while you monitor

connector J1/P1.

the status screen on ET.

C. Fabricate a jumper wire 100 mm (4 inch) long.

Crimp a Deutsch pin to both ends of the wire.

Expected Result:

The switch status changes from On with the

D. Insert the jumper wire into terminal 18 (Input

jumper wire in place to Off when the jumper wire

Sensor Common #1) of the breakout T. Insert the

is removed.

other end of the jumper wire into terminal 47

(Ignore Brake/Clutch Switch) of the breakout T.

E. Connect ET at the cab data link connector.