Retrieving Codes
- Perform diagnostic circuit check before diagnosing vehicle using self-diagnostic system. See appropriate DIAGNOSTIC CIRCUIT CHECK chart under DIAGNOSTIC CODE CHARTS .
- Fault codes can be retrieved using a scan tester connected to Data Link Connector (DLC) or by counting flashes of Malfunction Indicator Light (MIL) after grounding either DIAG SW connector in fuse block or diagnostic request terminal in duty check data link connector, located on left side of firewall. See Fig 1 .
- To retrieve code(s) using DIAG SW connector in fuse block, remove spare fuse from fuse block and insert into DIAG SW connector terminal. See Fig 1 . Turn ignition on and observe MIL to read fault code(s). Proceed to appropriate chart(s) under DIAGNOSTIC CODE CHARTS to diagnose fault codes.
- To retrieve code(s) using the duty check data link connector, connect jumper between duty check data link connector terminals No. 2 and 4. See Fig 1 . Turn ignition on and observe MIL to read fault code(s). Proceed to appropriate chart(s) under DIAGNOSTIC CODE CHARTS to diagnose fault codes.
- If no fault codes are stored, MIL will flash Code 12, indicating ECM diagnostic system is operating. If fault codes are stored, code will flash 3 times, starting with the lowest code. Proceed to appropriate chart(s) under DIAGNOSTIC CODE CHARTS to diagnose fault codes.
FAULT CODE IDENTIFICATION
| Code | Circuit Affected | Probable Cause |
|---|---|---|
| 13 | Oxygen Sensor | Signal Voltage Does Not Change |
| 14 | Coolant Temperature Sensor | Low Temperature Indicated |
| 15 | Coolant Temperature Sensor | High Temperature Indicated |
| 21 | Throttle Position Sensor | Signal Voltage High |
| 22 | Throttle Position Sensor | Signal Voltage Low |
| 23 | Intake Air Temp. Sensor | Low Temperature Indicated |
| 25 | Intake Air Temp. Sensor | High Temperature Indicated |
| 31 | MAP Sensor | Low Voltage Input |
| 41 | Ignition Signal | No Signal |
| 42 | Camshaft Position Sensor | No Signal |
| 51 | EGR System | EGR VSV Inoperative |