Centinel System – Master Repair Manual – 019-026   Data Link Circuit, Public

Heavy-Duty Only

To communicate with the Centinel™ control module, the public datalink circuit is used for an electronic service tool.

NOTE: No service tool is provided for Heavy-Duty applications. The Centinel™
control module will use the public datalink.

For Celect™ Plus engines, the datalink is powered and uses a 6-pin Deutsch connector. (For Celect™ engines, the public datalink is accessed by the control harness through splices in the cab.) The wiring positions follow:

Position A – Datalink (+)

Position B – Datalink (-)

Position C – Battery (12 or 24 VDC)

Position D – Open

Position E – Block ground

Position F – Not used.

CAUTION  Use test lead, Part Number 3822758, on the Centinel™ control module connector and use test lead, Part Number 3823993, on the 6-pin Deutsch connector to avoid damage to the connector pins.

Disconnect the harness connector from the Centinel™ control module and the Deutsch 6-pin connector.

Turn the keyswitch to the “OFF” position.

Measure the resistance from pin 8 (Heavy-Duty) or pin 6 (High-Horsepower)
of the Centinel™ control module harness connector to pin A of the 6-pin Deutsch connector (or the proper wire splice for the Celect installation).

The multimeter must show a closed circuit (10 ohms or less).

If the circuit is not closed, repair or replace the Centinel™
harness. Refer to Procedure 019-131.

Measure the resistance from pin 9 (Heavy-Duty) or pin 8 (High-Horsepower)
of the Centinel™ control module harness connector to pin B of the 6-pin Deutsch connector (or the proper wire splice for the Celect™ installation).

The multimeter must show a closed circuit (10 ohms or less).

If the circuit is not closed, repair or replace the Centinel™
harness. Refer to Procedure 019-131.

CAUTION  Use test lead, Part Number 3823993, for the 6-pin Deutsch connector to avoid damage to the connector pins.

Disconnect the harness connector from the Centinel™ control module.

Measure the resistance from pin A of the Deutsch connector or pin 8 of the Centinel™ control module harness connector to the engine block.

The multimeter must show an open circuit (1M ohms or more).

If the circuit is not open, repair or replace the Centinel™
harness. Refer to Procedure 019-131.

Measure the resistance from pin B of the 6-pin Deutsch connector or pin 9 of the Centinel™ control module harness connector to the engine block. The multimeter must show an open circuit (1M ohms or more).

If the circuit is not open, repair or replace the Centinel™
harness. Refer to Procedure 019-131.

Measure the resistance from pin B to all other pins in the connector. The multimeter must show an open circuit (1M ohms or more).

If the circuit is not open, repair or replace the Centinel™
harness. Refer to the appropriate base engine troubleshooting and repair manual.

Measure the resistance from pin C to all other pins in the connector. The multimeter must show an open circuit (1M ohms or more).

If the circuit is not open, repair or replace the Centinel™
harness. Refer to the appropriate base engine troubleshooting and repair manual.

Locate the datalink connector on the Centinel™ harness. The location will depend on the installation procedures.

CAUTION  Use test lead, Part Number 3823993, for the 6-pin Deutsch connector to avoid damage to the connector pins.

Turn the keyswitch ON.

Turn the dial on the multimeter to measure DC voltage.

Measure the voltage from pin 8 of the Centinel™ control module harness connector to the engine block. The multimeter must show 2.5 to 5 VDC.

Measure the voltage from pin 9 of the Centinel™ control module harness connector to the engine block. The multimeter must show 0 to 2.5 VDC.