Skip the auto shop - Our mechanics make house calls

Q: Car will not turn off - 1991 Jeep Grand Wagoneer

asked by on

I can’t get my jeep to turn off. It starts well and runs in perfect condition. I put in a new ignition switch, starter relay, but it still won’t turn off. I read somewhere that if you start the engine then turn the key to OFF then pull the plug on the back of the alternator the car turns off – the problem is with the alternator. Is this true? Do you have any other ideas on this?

A: Your reading heads you in the correct direc...

Your reading heads you in the correct direction! SOMETHING, perhaps the alternator, is "back-feeding" power to the ignition, injection, etc. Back-feeding is using an electrical circuit in reverse, and inappropriately. There is a short, or other electrical abnormality causing this problem. A bad ground (engine to chassis) can sometimes also cause this problem. A professional mechanic, like a certified technician from, YourMechanic, can diagnose this problem and repair and replace the problem component.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: My car cranks and seems to fire once but won't start - 1991 Toyota Tercel

Hi there. From the description you have provided, these symptoms need to be properly diagnosed. Replacing parts, without diagnoses, can be expensive and time consuming. Assuming the engine is mechanically sound, the description you provided about the spark plug condition...

Q: Micra 1.2 first MOT says I need a new wishbone OSF AND a new alternator belt.

Hello. From your description it sounds like you need a belt and part of the wishbone suspension. Some places also call the torque mount on the engine a wishbone. The alternator belt is not too unusual at this age and...

Q: Can the replacement of the ignition switch cause the air conditioning to stop cooling?

Hello. To replace the ignition switch, the Technician would have been "near" the dash. The only possible connection would be if he did something to block or de-activate the air passages, blend door, or related controls or the A/C. If...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...