Skip the auto shop - Our mechanics make house calls

Q: CEL transmission slipping

asked by on

My truck is a carpet cleaning truck. And I am not sure if my equipment has anything to do with the problems I am having. But I have been getting this code: P2534 - ignition 1 switch circuit low voltage - off and on for months. When I am driving 45 mph my engine was at 2900 rpms. Is that second gear? I had not used my carpet cleaning equipment after the code was cleared the last time. When I drove up a hill my transmission slipped. I let off the gas and it feathered a little until it shifted back into gear. It was fine after that with no Check Engine Light. But today as I was driving down the freeway, and I hit a bump that caused the transmission to slip again. When it shifts back then the Check Engine Light comes on. Then approximately 10 minutes later I was at a stop light. When I accelerated it didn’t go into first gear. I am stuck in whatever gear it’s in. At the next stop light I turned the van off then back on, and it shifted OK until I got home. What’s causing my truck’s problems and how can I fix it?

A: Hi there. You definitely appear to have a v...

Hi there. You definitely appear to have a voltage issue with the vehicle. From what you are can be a bad connection at the battery, a failing alternator, or most commonly a bad ignition switch.

I usually start by checking the battery and the alternator first. If both of those are fine then I do a voltage drop test of the ignition switch. The ignition switch is the most common issue I have seen on this vehicle. If the switch is fine then it may have a bad connection someplace else, like the fuse box.

If are going to have this looked at, consider YourMechanic, as a certified mechanic can come to you home or office to diagnose the Check Engine Light and repair this.

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・Save up to 30%

Get a quote

What others are asking

Q: My car is idling rough

It is a possibility that the engine performance issues may have been caused by a problem when it putting the pieces back together, however, the trouble codes seem to point to different issues. Both codes are related to the oxygen...

Q: Can a misfire problem stall out the motor?

It is highly unlikely that failed ignition coils would cause any mechanical engine damage, or your engine itself to fail. Coil packs can and do fail after so many miles, with no particular mileage being an “average” - and not...

Q: Starts intermittently

This may be related to many different possibilities, some of which may be related to a lack of spark and some of which may be related to a fuel delivery problem or a combination of both. For example, if the...

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...
How to Renew Your Car Registration in Oklahoma(DELETED)
Having your car registered with the Oklahoma Tax Commission is an important part of driving legally in this state. You will need to do this within 30 days of moving to Oklahoma...
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...