Circuit Description
The control module controls the shift lamp using the following inputs:
| • | The Engine Coolant Temperature (ECT) sensor |
| • | The Throttle Position (TP) sensor |
| • | The Vehicle Speed sensor (VSS) |
| • | The Engine RPM |
The control module uses the measured RPM and the vehicle speed in order to calculate what gear the vehicle is in. This calculation determines when the shift lamp should be turned ON.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Was the On-Board Diagnostic (OBD) System Check performed? | -- | Go to Powertrain On Board Diagnostic (OBD) System Check for 2.2L Powertrain On Board Diagnostic (OBD) System Check for 4.3L | ||
2 |
Is the shift lamp ON? | -- | ||
3 |
Is the shift lamp ON? | -- | ||
4 | Using the scan tool, command the shift lamp OFF and ON. Does the shift lamp respond to the scan tool command? | -- | System OK | |
5 | Check the terminal connect at the control module for the shift lamp control circuit. Was a problem found? | -- | ||
6 | Repair the open in the shift lamp circuit. Is the action complete? | -- | -- | |
7 | Repair as necassary. Is the action complete? | -- | -- | |
8 |
Is the shift lamp ON? | -- | ||
9 | Repair the short to ground in the shift lamp control circuit. Is the action complete? | -- | -- | |
10 | Replace the control module. If the control module is faulty, the new controller must be programmed. Refer to Powertrain Control Module Replacement/Programming for 2.2L and EEPROM Programming for 4.3L. Is the action complete? | -- | -- | |
11 |
Are any additional DTCs displayed? | -- | Go to Applicable DTC | |
12 | Using the scan tool, select Capture Info, Review Info. Are any additional DTCs displayed that have not been diagnosed? | -- | Go to Applicable DTC | System OK |
