Test Step 6. Check the Wire Harness for the Coolant Level Low

192

TM 9-2320-312-24-2

Troubleshooting Section

E. Measure the voltage at the breakout T from

B. Use a jumper wire in order to connect terminal A

terminal 2 to terminal 5.

(coolant level low) and terminal D (coolant level

normal) to terminal B (sensor common) at the

Refer to Illustration 59.

harness connector.

Refer to Illustration 55.

Expected Result:

The measured voltage is between 4.5 VDC and 5.5

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

VDC.

D. While the jumper wires are in place, access the

active diagnostic code screen on Cat ET.

Results:

Yes The problem is located in the harness

E. Verify that 111-02 Coolant Level Sensor Fault

(12) is active.

wiring.

Note: Wait for 30 seconds for the activation of the

Repair: Repair the wiring or replace the wiring,

diagnostic code.

as required.

Verify that the repair eliminates the problem.

Expected Result:

111-02 Coolant Level Sensor Fault (12) is active

STOP.

while the jumper wires are in place.

No The problem is on the ECM side.

Results:

Repair: Temporarily connect a test ECM. Ensure

Yes The harness and the ECM are working

that the "Engine Monitoring" and the "Coolant

Level Sensor" are programmed to match the

correctly.

old ECM. Check the test ECM by measuring

the voltage at the breakout T from terminal 2 to

Repair: Remove the jumpers. Replace the sensor

terminal 5 again. If the problem is resolved with

and ensure that 111-02 Coolant Level Sensor

the test ECM, reconnect the suspect ECM. If the

Fault (12) disappears with the new sensor.

problem returns with the suspect ECM, replace

the ECM.

Verify that the repair eliminates the problem. Clear

all diagnostic codes.

STOP.

Test Step 6. Check the Wire Harness for

the Coolant Level Low

No Proceed to Test Step 7.

g00651008

Illustration 55

Jumper wire

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