Test Step 4. Insert a Jumper Wire at the Switch -807640454

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TM 9-2320-312-24-2

Troubleshooting Section

Results:

Expected Result:

YES

The "Switch Status" changes to "ON" with the

jumper wire in place. The "Switch Status" changes

to "OFF" when the jumper wire is removed.

Repair: Perform the following diagnostic

procedure:

Results:

Replace the fast idle switch.

Yes The ECM is functioning properly at this

Verify that the repair eliminates the problem.

time. Proceed to Test Step 4.

No The ECM is not functioning properly.

STOP.

NO There is a problem in the wire harness

Repair: Perform the following repair:

between the fast idle switch and the ECM.

1. Temporarily connect a test ECM.

Proceed to Test Step 5.

Test Step 5. Insert A Jumper Wire At The

2. Remove all jumpers and replace all connectors.

Bulkhead Connector.

3. Recheck the system for Active diagnostic

codes.

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

4. Repeat the test step.

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

Crimp a Deutsch pin to both ends of the wire.

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

reconnect the suspect ECM.

C. Locate the socket for the fast idle switch in the

engine side of the bulkhead connector for the

6. If the problem returns with the suspect ECM,

wiring to the ECM.

replace the ECM.

D. Insert the wire jumper pin between the switch

7. Verify that the repair eliminates the problem.

socket and the sensor common connection.

Install the jumper wire on the engine side of the

STOP.

bulkhead connector for the wiring to the ECM.

Test Step 4. Insert a Jumper Wire at the

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

Switch.

F. Alternately connect and then disconnect the

jumper wire. At the same time, monitor the

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

"Status Screen" on the Electronic Service Tool.

B. Reconnect the ECM vehicle harness connector

J1/P1.

Expected Result:

The "Switch Status" changes from "ON" with the

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

jumper wire in place. The "Switch Status" changes

Crimp a Deutsch pin to both ends of the wire.

to "OFF" when the jumper wire is removed.

D. Insert the jumper wire between the two switch

terminals of the fast idle switch.

Results:

YES The problem is in the vehicle wiring

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

between the bulkhead connector and the switch.

F. Alternately remove the jumper wire and then

Inspect the vehicle wiring and then repair the

insert the jumper wire at the switch terminals. At

vehicle wiring. Otherwise, send the vehicle to

the same time, watch the "Status Screen" on the

the OEM dealer for repair. Verify that the original

Electronic Service Tool.

condition is resolved. STOP.

NO The problem is in the vehicle wiring

Expected Result:

between the bulkhead connector and the ECM.

The "Switch Status" changes to "ON" with the

Inspect the vehicle wiring and then repair the

jumper wire in place. The "Switch Status" changes

vehicle wiring. Otherwise, send the vehicle to

to "OFF" when the jumper wire is removed.

the OEM dealer for repair. Verify that the original

condition is resolved. STOP.