Skip the auto shop - Our mechanics make house calls

Q: Transmission problem after alternator replacement

asked by on

Hi, I had an alternator replaced 3 weeks ago. Afterwards, I noticed that the transmission couldn't shift to higher gears when driving at higher speeds. RPM was also very high. This persisted for 2 days and then went away. Just the other day, the transmission problem reoccurred while I was driving. The car then came to a stop and I was not able to get it accelerating again. I powered off the car and started it back up and was able to drive at a low speed. I've been finding similar cases online where a low battery or a bad alternator caused similar transmission problems. The explanation is that not enough voltage is being supplied to the electronic transmission control, which leads it to send out no signal or a wrong signal. This then triggers the vehicle to go into limp mode. Given the symptoms and the transmission problem coinciding with the alternator replacement, is it possible that this could be a potential cause for my transmission problem? Thanks!

My car has 113000 miles.
My car has an automatic transmission.

Hi there. Why was the alternator replaced? Was the battery tested with a digital tester that provides current voltage, cold cranking amps, and state of health? If not, I suggest having that battery tested. A bad cell inside the battery can wreak havoc on electrically controlled systems; especially computer controlled systems. This cell can create voltage spikes and dips where there should be none. I suggest having a qualified technician perform an inspection to avoid replacing unnecessary parts. Your Mechanic has several available technicians that can assist you with an electrical problems inspection.

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

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: Starts but wont move or rev up after replacing battery 2005 Ford Explorer

Hi there - your symptoms suggest a problem with the throttle position sensor. Check for problem codes - whether the Check Engine light is on or not - I would expect some indication of a problem here. Changing the battery...

Q: What should I know about driving while towing a trailer?

Towing a trailer while driving means that you have a lot of additional things to worry about. You have a lot of extra length, your turns need to be wider, you have to make sure that the lane is clear...

Q: We have Cadillac DTS when driving a short distance the car will not accelerate over 45 an overheating won't Hold antifreeze

It sounds like you may have a blown cylinder head gasket. A blown head gasket may cause a number of different symptoms. A head gasket that fails between cylinders will generally cause a misfire and potentially compression leaks from one...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
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...
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.