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.
1990 Oldsmobile Custom CruiserFACTORY OEM SERVICE PROCEDURE
Control Switch Test
- Put ignition switch in RUN position. With tailgate power window control switch connector connected, measure voltage between Pink wire at control switch connector and ground. If battery voltage is not present, check/repair Pink wire for an open.
- Put tailgate power window control switch in RAISE position. Check voltage between Light Blue wire at control switch connector and ground. If battery voltage is not present, replace tailgate power window control switch.
- Put tailgate power window control switch in LOWER position. Measure voltage between Tan wire at control switch connector and ground. If battery voltage is not present, replace tailgate power window control switch.
Factory Service Tools
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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.