Test Step 3. Connect ET and Check the Solenoids and the Relays

270

TM 9-2320-312-24-2

Troubleshooting Section

Troubleshooting, "Accelerator Pedal (Throttle)

Expected Result:

Position Sensor Circuit - Test".

All of the solenoids and all of the relays are

operating.

STOP.

Not OK Clutch switch status is incorrect.

Results:

Yes The ECM is operating correctly. STOP.

Repair: Perform the following diagnostic

procedure:

No Proceed to Test Step 4.

Troubleshooting, "Clutch Pedal Position Switch

Test Step 4. Use ET to Check the ECM.

Circuit - Test".

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

STOP.

Test Step 3. Connect ET and Check the

B. Disconnect the ECM engine harness connector

Solenoids and the Relays.

J1/P1.

C. Connect a breakout T to the ECM connector

J1/P1.

D. Connect a voltage test lamp to terminal 12

(Output 3) and terminal 65 (-battery) of the

70-Terminal breakout T.

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

F. Access the special test for the "Exhaust Brake

Special Test" on ET.

G. While the voltage test lamp is being observed,

cycle the special test for the exhaust brake to

the ON and OFF positions.

H. Stop the special test.

Expected Result:

The voltage test lamp behaves in the following

g00769913

Illustration 102

manner:

Breakout T

The voltage test lamp turns on when the test is

A. Connect ET at the cab data link connector.

active.

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

The voltage test lamp turns off when the test is

not active.

C. Turn the switch ON for the exhaust brake.

Results:

D. Access the status screen on ET for the "Exhaust

Brake Special Test".

Yes There is a problem in the harness.

E. Turn the on/off switch for the exhaust brake to

Repair: Perform the following repair:

the ON position.

Repair the engine harness or replace the engine

F. Begin the "Exhaust Brake Special Test" while you

harness. Verify that the repair eliminates the

listen for the solenoids to click. You may need to

problem.

be closer to the engine in order to hear the click

of the solenoid.

STOP.