For 1990-2009 cars

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the System Check? | -- | Go to Step 2 | Go toData Link Communications System Check
2 | Attempt to establish communication with the same system on a different vehicle. Can you establish communication? | -- | Go to Step 3 | Go to Step 4
3 |

1. Turn the ignition switch to the OFF position.
2. Inspect for the correct connection of the scan tool to the data link connector.

Is the connection good?

--

Go to Step 5

Go to Step 6

4 | The scan tool may be malfunctioning. Refer to Scan Tool Instruction Manual. Is the repair complete? | -- | Go toData Link Communications System Check | --
5 | Measure the resistance of the data link connector (DLC-OBD II) from terminal 7 to terminal 5. Does the J 39200 display OL? | -- | Go to Step 7 | Go to Step 8
6 | Repair the data link connector terminal 7, or reconnect the scan tool as necessary. Is the repair complete? | -- | Go toData Link Communications System Check | --
7 | Measure the voltage of the data link connector (DLC-OBD II) from terminal 7 to terminal 5. Did you measure any voltage? | -- | Go to Step 10 | Go to Step 9
8 | Repair a short to ground in the PPL wire or in the PPL/WHT wire between the following components:

• | The Powertrain Control Module (PCM)

• | The data link connector (DLC-OBD II)

Is the repair complete?

--

Go toData Link Communications System Check

--

9 | Measure the voltage on the data link connector (DLC-OBD II) from terminal 16 to ground. Did you measure the system voltage? | -- | Go to Step 11 | Go to Step 12
10 | Repair a short to voltage in the PPL wire or in the PPL/WHT wire between the following components:

• | The PCM

• | The data link connector (DLC-OBD II)

Is the repair complete?

--

Go toData Link Communications System Check

--

11 |

1. Inspect the PPL wire or the PPL/WHT wire for an open between the following components:

• | The PCM

• | The data link connector

2. If the wires are OK, refer to Engine Controls in order to diagnose the PCM.

Is the repair complete?

--

Go toData Link Communications System Check

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12 | Repair the open in the WHT wire between the junction block and the data link connnector. Is the repair complete? | -- | Go toData Link Communications System Check | --