PT Cruiser Forum  

Go Back   PT Cruiser Forum > General Forums > Tech & Performance Forum

PT Cruiser Forum

Odometer fault codes are inaccurate?

LinkBack Thread Tools Display Modes
  #1 (permalink)  
Old 15 Aug 2011, 01:45 pm
Fresh Cruiser
Join Date: Aug 2011
Location: Indiana
Posts: 26
Default Odometer fault codes are inaccurate?

We have an '02, and the Check Engine light has been on for a while now. We've not noticed even the slightest change in operation. One shop said the error code related to a bad ECM, and the dealer would have to replace it.

I read that you could get the fault code on the odometer by cycling the key back and forth within five seconds, and I did that. Problem is, the code, 1601, as stated by the dealer, is a "ghost" code and absolutely meaningless. I was told that the codes displayed on the odometer are invariably inaccurate. Is that true?

Anyway, it's an '02 with just 54K on it. Does the ECM typically fail around 9 years?
Reply With Quote
  #2 (permalink)  
Old 15 Aug 2011, 01:54 pm
Cool Cruiser
Join Date: Nov 2007
Posts: 394
Default Re: Odometer fault codes are inaccurate?

I've never seen an ECM (more accurately PCM - powertrain control module) actually fail outright.

P1601 Serial Comm. Problem With Device 1
another place has it as:
P1601 ECM/TCM Serial communication error

No clue what that means. All codes mean "something", they didn't engineer a vehicle that just decided one day to report an error that meant nothing at all. Even the oft-reported P1684 (which is the battery has been disconnected in the past 50 starts) - means "something".

To me at first glance - it means the transmission module and the engine module aren't communicating. It could be as simple as that it isn't plugged in, a bad wire somewhere, bad connector, bad TCM OR bad ECM (in that the serial transceivers used to communicate has failed).

The only time there is a difference in what is displayed in the OD, and a scantool - is if one of those codes is P0700. That indicates a "transmission control module has stored codes" - as the TCM has a different code set. Those aren't displayed in the OD. No codes exist unless you have a P0700 first. Invariably what is displayed on the OD, are what the PCM has stored as trouble codes.

One thing to try - remove the negative terminal connector on the battery. Wait a while (15 minutes or mor) - and reconnect. This clears any trouble codes. If the code persists, it has just been set.

Last edited by bobdole369; 15 Aug 2011 at 01:58 pm.
Reply With Quote
  #3 (permalink)  
Old 15 Aug 2011, 02:24 pm
Obsessed Cruiser
Join Date: Sep 2001
Posts: 27,758
Default Re: Odometer fault codes are inaccurate?

I think you guys mean P0601 instead of 1601.....................................

P0601 - PCM internal controller failure.

When monitored = ignition key on.

Set condition = internal checksum for software failed, does not match calculated value.

Possible causes = PCM (no other causes)

Test = none. The PCM is reporting internal errors and must be replaced.

By all means get a second opinion on this, perhaps through the DC dealer

Last edited by CREWZIN; 15 Aug 2011 at 03:02 pm.
Reply With Quote
  #4 (permalink)  
Old 15 Aug 2011, 03:00 pm
rcktpwrd's Avatar
Senior Cruiser
Join Date: Jan 2011
Location: Raleigh, NC
Posts: 1,867
Default Re: Odometer fault codes are inaccurate?

A few years ago the check engine light came on in mine, did the key dance and got a code that said the PCM had an internal fault. I don't remember what code it was. The car ran perfectly normal but it would not pass the state emissions test because the light was on. The only fix was to replace the PCM, fortunately for me the car was still covered by the Federal emissions warranty so it was replaced at no cost to me.

2001 PT Cruiser 5-speed; 1976 Oldsmobile Cutlass S; 1990 Chevy 454SS; 1995 Caprice Classic woody
Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Fault Codes sscanlan Tech & Performance Forum 11 29 Sep 2010 09:53 pm
Won't Start---Can't get fault codes patspt Turbo Performance 8 01 Jun 2010 04:47 pm
Clearing fault codes thender Tech & Performance Forum 2 08 Nov 2009 08:00 pm
How to retrieve fault codes. CREWZIN Tech & Performance Forum 0 11 Jul 2009 09:52 am
Whats the difference between key trouble codes vs odometer ones? sknight88 Tech & Performance Forum 10 22 Jun 2008 04:56 pm

All times are GMT -5. The time now is 11:28 am.

Powered by vBulletin® Version 3.8.2
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
LinkBacks Enabled by vBSEO 3.6.0 PL2 © 2011, Crawlability, Inc.