Skip the auto shop - Our mechanics make house calls

Q: Car won't start, is it my ECU?

asked by on

So, my car battery died because I left the keys in the ignition for 2 weeks, not in the on position, just in the ignition. So we jumped it & all was well. Unfortunately I didn't drive it or let it run long enough, so in the morning it was dead again. So my boyfriend jumped it again, this time he crossed the cables & it caused a spark of course. He then put them on the correct way & the car started. We drove around fine but the radio wasn't working. I found that it blew the radio fuse. The radio came on but I have no sound with the radio, only sound on the right side when a cd is in. Well now the car tries to start but it won't fully turn over. Could it be the ECU? We got the P1122 code for the throttle control actuator & are going to look into the fuel pump & I will be getting a new battery but I just need to know what else it could be? Please help, I just got the car 2 months ago & have only driven it twice.

My car has 120000 miles.
My car has an automatic transmission.

A: Hi, thanks for writing in. While it could b...

Hi, thanks for writing in. While it could be the ECU, it could also be a great many other things. It is most likely not any one component but is probably a combination of faults. Many years ago you could get away with crossing the cables with little more damage than an alternator, but the electronics in modern cars are very sophisticated and are easily damaged by voltage spikes. You probably have a surge protector on your computer at home to protect it from just the sort of thing that happens to the electronics in your car if you get your cables crossed. There is no easy answer for this problem and simply replacing every component that shows up in the list of codes can get very expensive and very likely won’t solve all of your problems. This is one case where you really need someone with experience to sort it out. Here at YourMechanic, we can have a technician come to your home or office to inspect and diagnose this issue for you, and make or suggest the necessary repairs.

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 won't start. All the lights work, there is just a single loud click when I try to start it. Is it the starter?

If the starter is accessible under the hood, grab a friend and a small hammer. While one of you tries to crank the engine, have the other lightly tap the starter at the same time. It is possible the starter...

Q: Ccd player reads CD error

In order to diagnose the CD player for will not eject or load CD's then you will need to have the radio removed and the CD tray repaired and the repair shop will return your CD discs. There is no...

Q: Check engine light is on, shows cam sensor that I already replaced two times. Still the same code for camshaft sensor. It starts if I unplug cam sensor

Hello there, thanks for writing in. I'd be happy to help. If you replaced the sensor twice and the issue persists, then I would look at the connector and ECM as possible sources of the issue. I would carefully inspect...

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...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...