Skip the auto shop - Our mechanics make house calls

Q: Electrical power drops out completely while driving.

asked by on

2003 Jeep Grand Cherokee Laredo 4.0L 305,000+ miles. On startup in the morning, when I put the car in drive and stepped on the gas, electrical power would sometimes drop out completely, then comes back, then does it again sometimes 5 or 6 times (i.e., RPM's go to zero, gas gauge goes to empty, speedometer goes to zero, engine stops running, etc.). Wiggling the key always resolved the problem but sometimes it took several tries (and sometimes a couple of restarts) to find a "sweet spot". After it resolved it ran fine, but once in a great while it skipped a beat again. Throughout the day when I started it the same thing would happen, but not as bad. I have replaced the ignition switch with a new one from Standard Electrical Product. It greatly improved the situation, but sometimes it still happens. Question is, short of having gotten a defective ignition switch off-the-shelf, is there anything else that might cause this? (Bad relay somewhere, etc.) Thanks.

My car has 305000 miles.
My car has an automatic transmission.

A faulted automatic shutdown relay or asd relay is a common concern on your vehicle model and can show the same symptoms. I have seen this problem caused by the relay as well as corrosion inside the under hood fuse block so that would be a good place to start looking around. Consider hiring an experienced technician like one from YourMechanic who can come out and take a closer look at your loss of power or stalling concerns and offer a more personal diagnosis.

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
  1. Home
  2. Questions
  3. Electrical power drops out completely while driving.

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: Spark plug closest to firewall /on 4.0 grand cherokee has oil on it

If you are getting oil in the back cylinder then you either have excessive oil getting into cylinder from valve seals from low oil flow in the valve cover area from too thick of oil or lack of oil changes....

Q: Transmission does not shift properly

This may be a sign of low transmission fluid or a faulty transmission control solenoid. As you know, automatic transmissions use pressurized hydraulic fluid to change gears. Every time a gear change is required, the car's computer activates a transmission...

Q: Engine turns over but won't start. Could it be a sensor and how do I check?

Hi there. There is a possibility that no power is being supplied from the ignition switch to the power distribution center fuse. The ASD relay fuse may have blown on the ground "control" side of ASD relay. Circuit tests need...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
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...
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...