Electrical Connectors

236

TM 9-2320-312-24-2

Troubleshooting Section

Verify that the repair eliminates the problem.

Expected Result:

The ECM allows the parameters that are listed under

STOP.

the following active diagnostic code in the "Active

No The ECM is OK. STOP.

Diagnostic Code" screen to be programmed:

Test Step 6. Use ET to Determine

253-02 Check Customer or System Parameters

Programming Requirements

(56)

Results:

A. Connect ET to the cab data link connector.

Yes

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

Repair: Ensure that the cause of all diagnostic

C. Check for active diagnostic codes.

codes is repaired.

Note: If the diagnostic code 253-14 is active,

STOP.

the "Truck Manufacturer" parameter must be

programmed.

D. Determine the type of chassis. If the engine is

Repair: Temporarily connect a test ECM. Ensure

installed in a General Motors chassis, program

that the test ECM will allow the programming of

the "Truck Manufacturer" parameter to GM. For

the Parameters. If the test ECM does not allow

any other chassis, program the parameter to

the programming of the Parameters, the old ECM

"Other".

is OK. Something is wrong in the vehicle wiring.

Check the battery supply circuit to the ECM and

Note: ET will indicate that the communication to the

repair, as required.

ECM must be reestablished in order for the change

in the parameter to take effect.

Verify that the repair eliminates the problem.

Expected Result:

STOP.

There are no active diagnostic codes.

Test Step 5. Use ET to Review Parameters

and Data.

Results:

Yes Diagnostic codes are active. Proceed to

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

the appropriate troubleshooting procedure for the

B. Check the active diagnostic codes and the

active diagnostic code. STOP.

logged diagnostic codes by using ET.

No The ECM has been properly programmed.

C. Review the Customer and System Parameters.

STOP.

D. Review the Engine Lifetime Totals.

i01720712

Electrical Connectors - Inspect

Expected Result:

The parameters and totals are scrambled.

SMCS Code: 1408-040-CY

Results:

System Operation Description:

Yes

Most electrical problems are caused by poor

connections. The following procedure will assist

Repair: Try to reprogram the suspect parameter

in detecting problems due to connectors. If a

or parameters. If the ECM does not maintain

problem is found in an electrical connector, repair

the parameters, temporarily connect a test

the connector and verify that the problem does not

ECM. Ensure that the test ECM will allow the

return. Do NOT cut connector wires unless terminals

programming of the parameters. If the test

are being replaced. Repair the connectors with

ECM does not allow the programming of the

a 1U-5804 Crimp Tool. The wedges on the DT

parameters, the old ECM is OK. Something is

connectors are easily removed with a 147-6456

wrong in the vehicle wiring. Check the battery

Removal Tool.

supply circuit to the ECM and repair, as required.