Q: Is my problem my ECM relay?

asked by on

My truck sometimes allow me to get to my destination but once there and ready to leave it will not crank. I've had to wait up to 1 hour before or maybe even 5 mins and it cranks up. While headed to the dealership it completely turned off on the highway. I had to have it towed home and now the battery is dead from trying to crank it.
My car's transmission is unknown to me.

Hello and thank you for contacting YourMechanic. First you will need to charge or replace your battery. Most of the time, if a battery has a burned cell or will not hold a charge, then it causes a lot of errors within the electronics of a vehicle.

Once you have a good battery, test drive the vehicle to see if any problems come back. If the problems come back, then check the wires to the battery and to the main fuse box to ensure that they are tight. Then check the power and ground wires to the ECM. If all of the wires are good, try wiggling the ignition switch to see if you can duplicate the problem without moving the vehicle. If the engine cuts out when moving the key around without turning off the engine, then the ignition switch needs replaced. If not, then the ECM needs replaced. If you need further assistance diagnosing the no start, then have a professional technician, like one from YourMechanic, help you with your vehicle.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1,000 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. Is my problem my ECM relay?

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: Jeep won't start.

Hello, thank you for writing in. The vehicle sounds like it is getting fuel pressure while starting or holding it while the vehicle is off. This does not necessarily mean that the fuel pump is sustaining pressure after the vehicle...

Q: ECM might need to be reprogrammed.

The message "start disabled" is telling me that the car is not allowing the car to start due to a security system fault. There are 2 likely causes for your issue. The first is a faulty transponder in your key....

Q: My car leaks antifreeze, but i cant figure out from where. It is a little at a time.

Hi there Typically leaking coolant from a water pump will cause the overheating problem you are experiencing. If the water pump is leaking coolant, or the coolant appears to be coming from the front of your car, it means the...

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...
What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.