Test Step 7. Check the Status of the Cruise Control Set/Resume Switch on ET

359

TM 9-2320-312-24-2

Troubleshooting Section

Test Step 7. Check the Status of the

The switch status changes from "OFF" to "ON"

Cruise Control Set/Resume Switch on ET.

when the jumper is in place.

Results:

Yes The input 1 (PTO on/off switch) of the ECM

is functioning correctly. The problem is in the

switches of the vehicle or the problem is in the

wiring of the vehicle.

Repair: Inspect the wiring. Select one of the

following options:

Repair the wiring or replace the wiring.

Send the vehicle to the OEM dealer for repair.

Verify that the repair eliminates the problem.

STOP.

No The ECM is not reading the switch status

change.

g00768798

Illustration 157

Repair: Perform the following diagnostic

ECM breakout T-connector

procedure:

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

1. Temporarily connect a test ECM.

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

2. Ensure that the "PTO Configuration" of the test

Crimp a Deutsch pin to both ends of the wire.

ECM matches the "PTO Configuration" of the

suspect ECM.

C. Disconnect vehicle harness connector P1 from

the ECM.

3. Remove all jumpers and replace all connectors.

D. Connect a breakout T to ECM connector J1 and

4. Recheck the system for active diagnostic

connect P1 to the breakout T.

codes.

E. Connect ET to the cab data link connector.

5. Repeat the test step.

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

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

while the engine is off.

reconnect the suspect ECM.

G. Access the status of the cruise control set/resume

7. If the problem returns with the suspect ECM,

switch on ET.

replace the ECM.

H. While the switch status is being observed on ET

8. Verify that the repair eliminates the problem.

install the jumper into the breakout T in order

to connect terminal 35 (Set) to terminal 5 (AP

STOP.

sensor/switch sensor common). Also, while the

switch status is being observed on ET remove

the jumper from the breakout T in order to

disconnect terminal 35 (Set) from terminal 5 (AP

sensor/switch sensor common).

I. While the switch status is being observed on

ET, install the jumper into the breakout T. This

connects terminal 44 (resume) to terminal 5

(AP sensor/switch sensor common). Also, while

the switch status is being observed on ET,

remove the jumper from the breakout T. This will

disconnect terminal 44 (resume) from terminal 5

(AP sensor/switch sensor common).