Q: Check Engine Diagnosis - Transmission controller Communication error codes

asked by on

Check engine light came on. Transmisson would not shift from low gear. Speedometer was not registering. Stopped and restarted car. Car operated normally. Check engine light went off. Car has been operating normally. Took car to Autozone. Following was reported: P0700(indicates transmission control system). Error Codes Read P0700 (Read Fault memory of control unit ETC; U0101 (Lost communication with TCM); P1603 (PCM Internal dual port RAM communication failure; P0882 (TCM Power input signal low); P0461 (Fuel level sensor A Circuit range/performance). Car has been operating normally for about a 7 weeks but am concerned that problem may return. Advised that transmission controller may need replacement. Your opinion is appreciated.

My car has 78079 miles.
My car has an automatic transmission.

Hello there, many different faults can cause this combination of codes on your 2006 Chrysler PT Cruiser.

When we see loss of communication codes with Transmission Control Module (TCM) internal faults, this usually means one of the following:

  • the TCM is failing
  • the TCM is not being supplied with enough power
  • the wiring to the TCM is faulty

Given that you have fuel codes as well, the first place a qualified technician should check is the battery, and to inspect the wiring of the vehicle. Then a Check Engine Light inspection should be done to asses the codes.

Was this answer helpful?
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. Check Engine Diagnosis - Transmission controller Communication error codes

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: Knocking/Rattling sound in the engine bay on startup.

It would be difficult to tell what is causing the noise without first inspecting the vehicle using a mechanic's stethoscope on various locations to determine exactly where the source of the sound is. However, it is possible that the noise...

Q: Whining when accelerating and slight grinding when letting off the gas.

Hi, thanks for writing in. I don't wish to 2nd-guess, but your symptom description suggests that either the differential or the transmission may have been run low on fluid, but was refilled after a couple of weeks? Not clear on...

Q: Hi. I have a problem with my 86 regal. My 307 will shake and smoke a little every morning after the car has sat over night.

Hi there. It sounds like the needle and seat in the carburetor is not sealing off correctly and making the fuel drip over when the engine is sitting. Try pumping the throttle 2 times after you shut the engine off...

Related articles

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...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
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...