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.
Self-Diagnostic System: Notes
Body Control Module (BCM) is equipped with a self-diagnostic system which detects system failures or abnormalities. When a malfunction occurs, BCM will store a numerical code. Malfunctions are recorded as history or current failures. Intermittent failures may be caused by problems with electrical circuit. If a visual inspection does not locate problem, vehicle may be driven with a DVOM attached to suspect circuit. Abnormal voltage or resistance readings when problem occurs indicates problem is within that circuit. However, a damaged Electronic Variable Orifice (EVO)/Passlock module can occasionally be the cause.
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.