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 BMW 325is AutomaticFACTORY OEM SERVICE PROCEDURE
Air Conditioning On Signal
- The test terminal is 40 and ground. Turn air conditioning switch ON and ignition switch ON. The correct test value should be battery voltage (approximately 12 VDC). After getting battery voltage go to step 2.
- The test terminal is 41 and ground. Turn air conditioning switch ON and ignition switch ON. Make sure ambient temperature is above 60°F (16°C). The correct test value should be battery voltage (approximately 12 VDC).
Factory Service Tools
Use the Manual With the Right Hardware
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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.
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