Test STO - Self-Test Output
NOTE:
Enter this test only when instructed by TEST STI.
CIRCUIT PIN IDENTIFICATION
| Circuit | Breakout Box Pin No. | PCM Pin | Wire Color |
|---|---|---|---|
| STO | 17 | 1G | Light Green/Red |
- Check System Integrity Visually check all wiring and connectors for evidence of damage, shorting or looseness. If a fault is found, repair as necessary. If no fault is found, go to next step.
2) Check For Open STO Wire Turn ignition off. Install breakout box, leaving PCM disconnected. Measure resistance between STO test pin at breakout box and PCM STO terminal at Data Link Connector (DLC). See Figure. If resistance is less than 5 ohms, go to next step. If resistance is at least 5 ohms, repair open PCM STO wire.
3) Check For Short In STO Wire Ensure ignition is off, breakout box is installed and PCM disconnected. Measure resistance between ground and STO test pin at breakout box. If resistance is more than 10,000 ohms, go to TEST PGC. If resistance is 10,000 ohms or less, repair short to ground in PCM STO wire.