Test Step 4. Disconnect the Sensor in order to Create an Open Circuit

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TM 9-2320-312-24-2

Troubleshooting Section

D. Install the jumper on the engine harness

Expected Result:

connector. Install one end of the jumper at the

sensor signal (terminal 1). Install the other end

A short circuit diagnostic code or an open circuit

of the jumper at the common connection for the

diagnostic code is active.

engine temperature sensor (terminal 2). Wait at

least 15 seconds for activation of the short circuit

Results:

diagnostic code.

Short Circuit A short circuit diagnostic code is

active at this time. Proceed to Test Step 4.

Expected Result:

Open Circuit An open circuit diagnostic code is

A short circuit diagnostic code is active when the

jumper is installed. An open circuit diagnostic code

active at this time. Proceed to Test Step 5.

is active when the jumper is removed.

Test Step 4. Disconnect the Sensor in

order to Create an Open Circuit.

Results:

OK The engine harness and the ECM are OK.

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

Repair: Perform the following repair:

B. Disconnect the sensor connector of the sensor

with the short circuit diagnostic code.

1. Temporarily connect the suspect sensor.

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

2. If the diagnostic code remains active, replace

Wait at least 15 seconds for activation of the

the sensor.

diagnostic codes.

3. Verify that the repair eliminates the problem.

D. Access the "Active Diagnostic Code" screen on

the electronic service tool. Check for an active

4. Clear all Logged diagnostic codes.

open circuit diagnostic code.

STOP.

Expected Result:

Not OK The open circuit diagnostic code

An open circuit diagnostic code for the

remains active with the jumper in place. The

disconnected sensor is now active.

most probable location for the open is in the

sensor common or the sensor signal wire in the

Results:

engine harness between the ECM and the sensor.

Remove the jumper. Proceed to Test Step 7.

OK A short circuit diagnostic code was active

before disconnecting the sensor. An open

Test Step 6. Determine if the Short Circuit

circuit diagnostic code became active after

is in the Connector or in the Sensor.

disconnecting the sensor. Proceed to test step 6.

Not OK There is a short circuit between the

A. Thoroughly inspect the connector for moisture.

sensor harness connector and the ECM. Leave

B. Inspect the seals and reconnect the sensor.

the sensor disconnected. Proceed to Test Step 7.

Test Step 5. Create a Short Circuit

C. If the short circuit diagnostic code reappears,

Between the Signal and the Common

the sensor is the problem.

Terminals at the Sensor Connector.

a. Temporarily connect a new sensor to the

harness, but do not install the new sensor in

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

the engine.

B. Fabricate a jumper wire150 mm (6 inch) long.

D. Check for a short circuit diagnostic code while

Crimp a Deutsch terminal to both ends of the

the new sensor is connected to the harness.

wire.

Expected Result:

C. Monitor the "Active Diagnostic Code" screen

before installing the jumper wire and after

The short circuit diagnostic code is not present

installing the jumper wire.

when a new sensor is connected.