Test Step 5. Check the Switch Circuit -807640409

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TM 9-2320-312-24-2

Troubleshooting Section

Test Step 5. Check the Switch Circuit.

Table 167

Table for Status of the Cruise Control Switch Input

Condition of Switch Circuit

Switch Status

Circuit

Terminal 59 Cruise/Idle On/Off Switch is Open.

OFF

Open

Terminal 59 Cruise/Idle On/Off Switch is connected to

Shorted

terminal 5.

Set Switch Terminal 35 is Open.

OFF

Open

Set Switch Terminal 35 connected to terminal 5.

Set Switch ON

Shorted

Resume Switch (Terminal 44) is Open.

OFF

Open

Resume Switch (Terminal 44) connected to terminal 5.

Resume Switch ON

Shorted

3. Recheck the system for active diagnostic

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

codes.

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

4. Repeat the test step.

Crimp a Deutsch pin to both ends of the wires.

5. If the problem is resolved with the test ECM,

C. Disconnect vehicle harness connector P1 from

reconnect the suspect ECM.

the ECM.

6. If the problem returns with the suspect ECM,

D. Connect a breakout T to ECM connector J1 and

replace the ECM.

connect P1 to the breakout T.

7. Verify that the repair eliminates the problem.

E. Install the jumper into the suspect switch socket

of the breakout T. Connect the other end of the

jumper to ECM connector P1 terminal 5 (ap

STOP.

sensor/switch sensor common) of the breakout T.

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

G. Connect ET to the cab data link connector.

H. Access the status screen.

I. While the switch status is being monitored on

the status screen slowly remove the jumper from

terminal 5 and slowly insert the jumper from

terminal 5 (ap sensor/switch sensor common).

Refer to Table 167.

Expected Result:

The switch status changes per the information in

Table 167.

Results:

Yes The ECM is functioning properly. Proceed

to Test Step 6.

No The ECM is not functioning properly.

Repair: Perform the following repair:

1. Temporarily connect a test ECM.

2. Remove all jumpers and replace all connectors.