Test Step 2. Check for Normal Operation of the Fast Idle Lamp

278

TM 9-2320-312-24-2

Troubleshooting Section

F. Depress the fast idle switch while the status of

Refer to Troubleshooting, "Electrical Connectors

the fast idle enable switch is being observed.

- Inspect" for details.

Also observe the fast idle lamp. Release the

fast idle switch. The fast idle lamp should turn

B. Perform a 45 N (10 lb) pull test on each of the

on when the fast idle switch is pressed and

wires in the ECM connector that are associated

released.

with the fast idle lamp.

G. Depress the service brake pedal. The fast idle

C. Check the ECM connector (allen head screw) for

lamp should turn off when the service brake is

the proper torque of 6.0 Nm (55 lb in).

applied.

D. Check the harness and wiring for abrasion and

for pinch points from the sensor to the ECM.

Expected Result:

The switch status changes per the above

Expected Result:

information. The fast idle lamp turns on and the fast

idle lamp turns off per the description above.

All connectors, pins, and sockets should be

completely coupled and/or inserted and the harness

and wiring should be free of corrosion, abrasion

Results:

or pinch points.

Yes The fast idle lamp is operating normally.

Results:

STOP.

OK Proceed to Test Step 2.

No The ECM is not reading the switch status

change. Proceed to Test Step 3.

Not OK

Test Step 3. Test the Fast Idle Lamp

Circuit.

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 2. Check for Normal Operation

of the Fast Idle Lamp.

A. Verify that a fast idle enable switch is installed.

B. Connect ET.

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

D. Access the ET status screen. Verify that the

following switches indicate the correct status:

The service brake switch 1 is off.

g00834351

Illustration 112

The service brake switch 2 is off.

Pin locations

The neutral switch is on.

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

The clutch switch is off.

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

Crimp a Deutsch pin to both ends of the wires.

If any of the switches do not display the indicated

status, fast idle will not activate.

C. Disconnect vehicle harness connector P1 from

the ECM.

E. Use the ET status screen to monitor the fast idle

switch and the fast idle rpm.

D. Insert the jumper into P1:31.