Diagnostic Aids
WARNING: This page does not describe the selected car, but rather 32 other vehicles, including the 2003 Mercury Sable, 2003 Mercury Mountaineer, 2003 Mercury Marauder, 2003 Mercury Grand Marquis, and 2003 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.
Perform this test when instructed during QUICK TEST or if directed by other test procedures. Only use this test to diagnose the following:
- HO2S & Sensor Connection
- Fuel Injector &/Or Fuel Injector Circuits
- Vacuum Systems
- Harness Circuits (HO2S, HO2S GND, INJ 1-10, VPWR & SIG RTN)
- Powertrain Control Module (PCM)
NOTE:
HO2S may be displayed on scan tool as O2S.
To prevent replacement of good components, be aware the following non-EEC areas may be cause of driveability concerns:
- Ignition System
- Faulty Evaporative Emission System
- EGR &/Or PCV System
- Air Intake System
- Engine Oil Contamination
- Fuel System
- Exhaust System Leaks Or Restriction
- Engine Cooling System