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Scan Tool Does Not Power Up




Scan Tool Does Not Power Up

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information






Circuit/System Description

The data link connector (DLC) is a standardized 16 cavity connector. Connector design and location is dictated by an industry wide standard, and is required to provide the following:

* Scan tool B+ voltage at terminal 16

* Scan tool ground at terminal 4

* Common ground at terminal 5

Diagnostic Aids

* The scan tool will power up with the vehicle OFF. Some devices however, will not communicate unless the vehicle is ON and the power mode master device sends the appropriate power mode message.

* If the B+ circuit, ground circuits, and connections of the data link connector are functioning properly, the malfunction must be due to the scan tool.

Reference Information

Schematic Reference

* Data Communication Schematics [1][2]Electrical Diagrams

* Control Module References Programming and Relearning

Connector End View Reference

Component Connector End Views Hybrid/EV Battery Pack X1

Description and Operation

Data Link Communications Description and Operation Description and Operation

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Programming and Relearning for scan tool information

Circuit/System Testing

1. Vehicle OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3 meters (9.8 feet) away from vehicle. It may take up to 2 minutes for all vehicle systems to power down.

2. Test for less than 2 ohms between each of the X84 data link connector ground circuit terminals listed below and ground.

* Ground circuit terminal 4

* Ground circuit terminal 5

If 2 ohms or greater

1. Vehicle OFF.

2. Test for less than 2 ohms in the ground circuit end to end.

If 2 ohms or greater, repair the open/high resistance in the circuit.

If less than 2 ohms, repair the open/high resistance in the ground connection.

If less than 2 ohms

3. Vehicle in Service Mode.

4. Verify a test lamp illuminates between the B+ circuit terminal 16 at the X84 data link connector and ground.

If the test lamp does not illuminate and the circuit fuse is good

1. Vehicle OFF.

2. Test for less than 2 ohms in the B+ circuit end to end.

If 2 ohms or greater, repair the open/high resistance in the circuit.

If less than 2 ohms, verify the fuse is not open and there is voltage at the fuse.

If the test lamp does not illuminate and the circuit fuse is open

1. Vehicle OFF.

2. Test for infinite resistance between the B+ circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If the test lamp illuminates

5. Refer to the scan tool user guide.