Question about 2000 Pontiac Bonneville

1 Answer

Po605 I pulled a po605 on the Bonneville, I'm not sure what it means, I have the book that says internal control module, read only memory (ROM) error. I understand that some kid ripped the stereo out and put an after market stereo in it. After causing what ever problem that was caused, the kid decided to put the original stereo back in. Now the car only runs if you hold the gas peddle down at about 4000 rpm's, but really rough. Can you please help get me closer to making the proper repairs to car. Thank you. Michael Anthony

Posted by on

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Top Expert:

    An expert who has finished #1 on the weekly Top 10 Fixya Experts Leaderboard.


    An expert that got 20 achievements.


    An expert that got 10 achievements.

  • Pontiac Master
  • 21,873 Answers

Generally speaking, code 605 is a problem with the computer itself.
Some possible issues can be the computer has a shorted circuit board, the computer can not communicate with other components or control modules, or something has happened to the motherboard inside.
In most cases the computer would need to be replaced, but tests would need to be run to make sure. It could also be a wiring problem in the main harness.
You would need a shop manual to get the test procedures for the code.

Posted on Apr 21, 2013

6 Suggested Answers

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017

  • 5568 Answers

SOURCE: 2004 Bonneville - Temperature Gauge is Erratic

Since there is no voltage applied with the ignition off, if the gauge is not dropping down all the way, it is the gauge that has failed.
Temperature sensors are frequent failures but they are not active when the car isn't powered up. They can be intermittant, high, low but with no power, the gauge itself should go to the minimum.  

Posted on Jan 19, 2009

  • 91 Answers

SOURCE: wiring after market stereo to factory wiring equipt with factory amp

you have to get the cable that conects your factory deck harness to the aftermarket deck, and that will allow you to use your factory speakers and amp, the wire harness is availiable at canadian tire or any stereo shop

Posted on May 06, 2009

  • 166 Answers

SOURCE: 2000 Bonneville runs rough when cold

you need to get it zone will do it for free but most of the time it a o2 sensor or coolant sensor

Posted on Jul 17, 2009

  • 736 Answers

SOURCE: 1996 Pont Grand Prix ---- P0303 again & again

wow have checked about everything .. the code is telling you that cylinder 3 is mis firing ... you agree that it is missing ... there has to be a problem with that cylinder .. i would check and recheck the ignition wire, plug, distributer cap, coil associated with that cylinder .. here is a couple of URLs that may or may not shed some light ..

Posted on Aug 17, 2009

  • 14036 Answers

SOURCE: 1992 Bonneville SSEI 3.8 supercharger making internal noise


Posted on Aug 26, 2009

Testimonial: "thanks for the information,after going to the pontiac bonneville site, found out the couplier is most likely worn and will be replacing"

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

2 Answers

2003 jeep liberty 3.7 po605 code what could be the problem

An internal computer problem. Read only memory. This is the factory defaults. These can't be erased by a tech. But can be by a system fault. You can get the computer online for about $160. Plug and play. Dealers 2 to 3 times this.

Oct 08, 2016 | 2003 Jeep Liberty

1 Answer

Transmission code P 605

Depending on the vehicle code P0605 "Internal Control Module Read Only Memory (ROM) Error" usually means the computer is failing or has failed.

Aug 30, 2014 | Cars & Trucks

2 Answers

Can you tell me what the codes PO605 and PO700 are? PT Cruiser 2001

P0605-------- Internal control module read only memory (ROM) Error
Have the computor checked.
P0700-------- Transmission control system
Better take it to a transmission shop and have that checked so they can pinpoint the problem.

Aug 27, 2011 | 2001 Chrysler PT Cruiser

1 Answer

I have a 2001 Chryler Concorde with a 2.7L engine. The engine light came on a gave me 2 codes... PO700 and PO605.. Can you help me by telling me what i can change?

P0700 indicates the transmission control module has a code in it. That code is P0605 which indicates a TCM internal memory error. While the TCM would probably be the leading suspect you can't rule out other possibilities like corroded connections, etc.

May 10, 2011 | Chrysler Concorde Cars & Trucks

1 Answer

Recently my check engine light came on and I did a diagnostic to find a P0607 error to appear. The code had read something about a power train control module. I will probably end up taking my car into the...

P0601 Internal Control Module Memory Check Sum Error
P0602 Control Module Programming Error
P0603 Internal Control Module Keep Alive Memory (KAM) Error
P0604 Internal Control Module Random Access Memory (RAM) Error
P0605 Internal Control Module Read Only Memory (ROM) Error
P0606 ECM/PCM Processor
P0607 Control Module Performance
P0608 Control Module VSS Output "A"
P0609 Control Module VSS Output "B"
P0610 Control Module Vehicle Options Error
The p0607 error says Control Module Performance. It has something to do with the Control Module for the powertrain as you indicated. But, you may be able to take your car to a transmission shop to alleviate the problem using a transmission expert.

I don't think that it doesn't have anything to do with the engine, itself, even though it's listed under a driveability related code.

Good luck on this repair.

Jan 14, 2011 | 2002 Dodge Stratus

1 Answer

I have a 2000 Chrysler Voyager. The engine light came on and the following troubleshooting code - PO700 and PO605. Can you tell me what these mean?

The P0605 is an internal failure in the transmission controller. This code sets when the tcm fails one of its internal self tests, and i think the only repair is to replace the module. P0700 is transmission control system malfunction

Nov 29, 2010 | 2000 Chrysler Grand Voyager

1 Answer

Trouble codes po340,po605.and po325 car will normaly idle and if you push the gas peddle to much it will bog out and die what could be the problem? I have put a new fuel pump in.

po325 knock sensor 1 malfunction po340 camshaft position sensor malfunction po605 internal control modular (rom) read only memory error check the wiring to the computer for proper connection and damage the computer (pcm) may be damaged or its program erased this happens sometimes when the connector is unplugged and the battery is hooked up the other two can be related (pcm) failure or could be a wiring problem po325 check knock sensor wiring and sensor and same for po340 crank sensor wiring and sensor good luck

Nov 15, 2009 | 1997 Infiniti.5 J30

1 Answer


P0605....Internal Control Module Read Only Memory (ROM) Error, replace the PCM.

Oct 08, 2009 | 2002 Chrysler Town & Country

2 Answers

Won't shift into high gear

po700 is the code in the pcm,telling you there is a code in the tcm( trans control module) po605 is a internal tcm error replace and program the trans control module

Sep 01, 2009 | 2002 Chrysler Town & Country

1 Answer

Po605 and po700

p0700 is a generic trans. code, so the problem if it is in the trans. would require further trans diag. so i would scan trans specific codes first. but in most cases when a chrysler tells you it is an internal controller fault you can believe it. just make sure which controller it is telling you has a fault!

May 18, 2009 | 1999 Dodge Caravan

Not finding what you are looking for?
2000 Pontiac Bonneville Logo

134 people viewed this question

Ask a Question

Usually answered in minutes!

Top Pontiac Experts


Level 3 Expert

75797 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22114 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

8152 Answers

Are you a Pontiac Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides