Scan Tool Does Not Power Up
Diagnostic Instructions
Diagnostic Fault Information
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
DLC B+
|
1
|
1
|
-
|
-
|
DLC Ground
|
-
|
1
|
-
|
-
|
1. Scan Tool Does Not Power Up
|
|
| |
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 ignition OFF. Some modules however, will not communicate
unless the ignition is ON and the power mode master module sends
the appropriate power mode message. |
| • |
If the B+ circuit, ground
circuits, and connections of the DLC are functioning properly, the
malfunction must be due to the scan tool. |
Reference Information
Schematic Reference
Data Communication Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Data Link Communications Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information.
Circuit/System Testing
| 1. |
Test for less than 2.0 Ω
between the ground circuits terminal 4 of the DLC and ground, and
terminal 5 of the DLC and ground. |
| ⇒ |
If greater than the specified range, test the
ground circuit for an open/high resistance. |
| 2. |
Ignition ON, verify a test
lamp illuminates between the B+ circuit terminal 16 at the DLC and
ground. |
| ⇒ |
If the test lamp does not illuminate, test the
voltage supply circuit for a short to ground or an open/high
resistance. |
| 3. |
If all circuits test normal,
refer to the scan tool user guide. |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the repair.
|
