1   Intermittent Fault Test

NOTE: For wiring information, see D1 - ECU DOES NOT COMMUNICATE WITH DST supporting information.

1.   Connect the DST

2.   Ignition ON

3.   Start the ECU Communication Software

DST doesn’t communicate with ECU: GO TO  2

DST communicates with ECU: Problem is intermittent. If no other codes are present, see INTERMITTENT FAULT

DIAGNOSTICS, in Group 160.

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2

Sensor Voltage Test

NOTE: For wiring information, see D1 - ECU DOES NOT COMMUNICATE WITH DST supporting information.

1.   Ignition OFF

2.   Disconnect any of the following:

·   Fuel temperature sensor

·   MAT sensor

·   ECT sensor

3.   Ignition ON.

4.   Using a multimeter, measure the voltage between both terminals of the selected sensor harness connector.

3.0 V or above:

GO TO  4

Below 3.0 V:

GO TO  3

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3   Power Supply Test

NOTE: For wiring information, see D1 - ECU DOES NOT COMMUNICATE WITH DST supporting information.

1.    Ignition OFF

2.   Disconnect 48-way ECU connector

3.   Ignition ON

4.    Using a multimeter, measure the voltage between a good ground and terminal G1 in the harness end of the 30 terminal half of the 48-way ECU   connector.

3.0 V or above:

Faulty ECU power fuse OR

Faulty ECU power wiring OR

Faulty ECU

Below 3.0 V:

Key-on signal wire open or shorted to ground  OR

Faulty ignition switch OR

Faulty key-on power fuse

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4   PDM Power Light

NOTE: For wiring information, see D1 - ECU DOES NOT COMMUNICATE WITH  DST

Power light ON:

GO TO  6

Power light OFF:

GO TO  5

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Test

supporting information.

1.  Ignition ON

2.  Note the power light on the Parallel Data Module  (PDM)

5 Open in Diagnostic Connector Ground Wire Test

NOTE: For wiring information, see D1 - ECU DOES NOT COMMUNICATE WITH DST supporting information.

1.    Ignition OFF

2.   Disconnect the diagnostic cable from the diagnostic connector

3.    Probe terminal A in the diagnostic connector with a test light connected to battery voltage.

Light ON:

Open or short to ground in diagnostic connector switched power wire.

Light OFF:

Open in diagnostic connector ground wire.

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6 Open in Harness Circuit Test

NOTE: For wiring information, see D1 - ECU DOES NOT COMMUNICATE WITH DST supporting information.

1.    Ignition OFF

2.    Disconnect 60-way ECU connector and diagnostic cable from the diagnostic connector

3.    Using a multimeter, measure resistance on the harness end of both connectors between:

·   Terminal D in the diagnostic connector and terminal B1 in the 60-way ECU connector

·   Terminal C in the diagnostic connector and terminal B2 in the 60-way ECU connector

All measurements 5 ohms or less:

GO TO  7

One or more measurements greater than 5 ohms:

Open in harness circuit OR

Connector terminals in wrong position

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7   CAN Resistance Test

NOTE: For wiring information, see D1 - ECU DOES NOT COMMUNICATE WITH DST supporting information.

1.   Ignition OFF

2.   60-way ECU and diagnostic connector still disconnected

3.   Using a multimeter, measure resistance between terminals C and D in the harness end of the diagnostic connector.

Between 45 - 75 ohms:

GO TO  8

Less than 45 or greater than 75 ohms:

Faulty or missing CAN terminator connector(s) OR

Open or short in CAN wiring harness

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8 CAN High and Low Voltage Test

NOTE: For wiring information, see D1 - ECU DOES NOT COMMUNICATE WITH DST supporting information.

1.   Ignition OFF

2.   Reconnect ECU 60-way connector

3.   Ignition ON

4.   Using a multimeter, measure voltage between a good chassis ground  and:

·   Terminal C in the diagnostic connector

·   Terminal D in the diagnostic connector

Both measurements between 1.5 - 3.5 V: Faulty ECU connection OR

Faulty diagnostic cable OR

Faulty diagnostic connector

OR

Faulty Parallel Port Data Module (PDM)

OR

Faulty diagnostic software/computer configuration

OR

Faulty ECU

Either measurement less than 1.5 V or greater than 2.5 V: CAN wiring shorted to ground or voltage

OR

Faulty ECU

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