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.
1989 Mazda 929FACTORY OEM SERVICE PROCEDURE
Circuit Opening Relay
- With relay connected, ensure specified voltage is present at relay terminals. See FUEL PUMP RELAY CIRCUIT VOLTAGES table. Circuit opening relay on 929 is behind the driver's side kick panel. On MPV, relay is mounted on ECU. ECU is under protective cover on passenger side floor.FUEL PUMP RELAY CIRCUIT VOLTAGES
Terminal Ignition "ON": Volts Ignition "OFF" Volts Idle Volts Fp 0 12 12 Fc 12 0 0 B 12 12 12 STA 0 12 0 E1 0 0 0 - If voltages are okay, remove relay from vehicle. Check relay operation using a 12-volt battery source and making resistance tests. See Fig 1 .
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.
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