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.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSFORD1988AEROSTAR VAN PASSENGER, AUTOMATICREPAIR AND DIAGNOSISELECTRICALCHARGING SYSTEMSALTERNATOR - MODELS W/INTEGRAL REGULATORBENCH TESTINGOPEN FIELD OR SHORT CIRCUIT TEST
1988 Ford Aerostar Van Passenger, Automatic
Open Field Or Short Circuit Test
1988 Ford Aerostar Van Passenger, AutomaticSECTION Open Field Or Short Circuit Test
- Perform test before alternator disassembly. Adjust ohmmeter to x1 scale. Place ohmmeter leads on regulator "A" blade terminal and regulator "F" screw head. See Fig 1 . Rotate alternator pulley and note reading. Reverse ohmmeter leads and repeat test.
- Reading should be between 2.2 and 100 ohms in one direction. Fluctuation may occur while pulley is turning. Reading should fluctuate between 2.2 and 9 ohms with leads reversed.
- Reading with approximately 9 ohms in one direction and no reading in the other indicates open brush lead, defective brushes or loose regulator-to-brush holder attaching screws.
- Reading of less than 2.2 ohms in both directions indicates a shorted rotor or defective regulator. Reading exceeding 9 ohms in both directions indicates a defective regulator or loose "F" terminal screw.
- Place one lead on alternator rear housing with remaining lead touching regulator "F" terminal. Note reading. Reverse leads and repeat test. Reading should be infinite in one direction and approximately 9 ohms with leads reversed.
- Reading less than infinite in both directions indicates a grounded brush lead or defective regulator. Reading exceeding 9 ohms in both directions indicates defective regulator or "A" terminal connection.
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
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.