626 2.5L (Using Breakout Box)
- Warm engine to normal operating temperature. Turn ignition switch off. Connect 104-Pin Breakout Box (49-UN01-130) between PCM and PCM harness connector. See Figure .
- Voltage Inspection
Turn ignition switch on. Measure voltage at PCM terminal No. 35 (right rear HO2S), 60 (right front HO2S), 61 (left rear HO2S) or 87 (left front HO2S). See HO2S VOLTAGE (626 2.5L) table. If voltage is not as specified, check wiring harness and connectors between PCM and HO2S. Also check intake-air system, fuel system and self-diagnostic system. Repair as necessary. If system or wiring harness problems are not present, replace HO2S. - HO2S Heater Resistance Inspection
Disconnect HO2S 4-pin connector. Using ohmmeter, measure resistance between HO2S 4-pin connector terminals "C" and "D". See Fig 1 . See HO2S HEATER RESISTANCE SPECIFICATION (626 2.5L) table. If resistance is not as specified, replace HO2S. If resistance readings are within specification, check related wiring harness and connectors.
HO2S VOLTAGE (626 2.5L)
| Application | Volts | ||
|---|---|---|---|
| Right Front HO2S | |||
| Ignition On | Less Than 1.0 | ||
| Acceleration | 0.5-1.0 | ||
| Deceleration | 0-0.5 | ||
| Idle | |||
| After Warm Up | 0.1-0.9 | ||
| Engine Cold | Less Than 0.5 | ||
| Left Front HO2S | |||
| Ignition On | Less Than 1.0 | ||
| Acceleration | 0.5-1.0 | ||
| Deceleration | 0-0.5 | ||
| Idle | |||
| After Warm Up | 0.1-0.9 | ||
| Engine Cold | Less Than 0.5 | ||
| Right Rear HO2S | |||
| Ignition On | Less Than 1.0 | ||
| Acceleration | About 0 | ||
| Deceleration | About 0 | ||
| Idle | |||
| After Warm Up | 0.1-0.9 | ||
| Engine Cold | About 0 | ||
| Left Rear HO2S | |||
| Ignition On | Less Than 1.0 | ||
| Acceleration | About 0 | ||
| Deceleration | About 0 | ||
| Idle | |||
| After Warm Up | 0.1-0.9 | ||
| Engine Cold | About 0 | ||