Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2002 Mercury Villager BaseFACTORY OEM SERVICE PROCEDURE
Diagnostic Aids
Perform this test when instructed during QUICK TEST or another SYSTEM TEST. This test is intended to diagnose the following:
- HO2S heater.
- HO2S and sensor connection.
- Vacuum systems.
- Fuel injector and/or fuel injector circuitry.
- Harness circuits; HO2S HTR, HO2S, HO2S, INJ1-6 and VPWR.
- PCM.
NOTE:
Vehicles with Federal emissions use HO2S-11 only.
HO2S, HTR, INJ1-6 & KAPWR CIRCUIT IDENTIFICATION
| Circuit | PCM Terminal No. | Wire Color |
|---|---|---|
| HO2S-11 | 48 | Light Green |
| HO2S-12 | 54 | Brown |
| HTR-11 | 99 | Black |
| HTR-12 | 102 | Yellow |
| INJ1 | 82 | Green/Orange |
| INJ2 | 89 | Green |
| INJ3 | 84 | Green/Red |
| INJ4 | 91 | Yellow/Violet |
| INJ5 | 86 | Yellow/Green |
| INJ6 | 93 | Gray/Blue |
| KAPWR | 80 | Yellow |
HO2S OPERATING SPECIFICATIONS
| Engine Operating Condition | PID Reading | |
|---|---|---|
| KOEO | ||
| HO2S-11 | Less Than 1 Volt | |
| HO2S-12 | Less Than 1 Volt | |
| Idle | ||
| HO2S-11 | Switches Between 0.0-1.0 Volt | |
| HO2S-12 | Switches Between 0.0-1.0 Volt | |
| Deceleration | ||
| HO2S-11 | 0.0-0.4 Volt | |
| HO2S-12 | 0.0-1.0 Volt | |
| Acceleration | ||
| HO2S-11 | 0.5-1.0 Volt | |
| HO2S-12 | 0.0-1.0 Volt | |
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.