PT Cruiser Forum  
Advertisements
       

Go Back   PT Cruiser Forum > General Forums > General PT Cruiser Discussions

PT Cruiser Forum

Advertisements
Speedometer troubles

 
Like Tree11Likes

Reply
 
LinkBack Thread Tools Display Modes
  #1 (permalink)  
Old 27 Feb 2019, 05:06 pm
Fresh Cruiser
 
Join Date: Jan 2008
Posts: 24
Default Speedometer troubles

Over the past few weeks, the speedometer on my 2002 PT Cruiser would sometimes jump up and down when starting the engine. It was intermittent and wouldn't happen when the engine was warmed up or by the time I'd get to the garage. So today, I'm driving down the road and the speedometer is on 0. Wouldn't move off that. Took it to the garage and the guy did this reset and it started working again. Only thing is, now it is very slow at going back to 0 when I come to a stop. Makes me wonder if it is accurate at all.

Reply With Quote
  #2 (permalink)  
Old 27 Feb 2019, 07:42 pm
Handy_Cruiser's Avatar
Obsessed Cruiser
 
Join Date: Oct 2013
Location: Arkansas
Posts: 10,094
Default Re: Speedometer troubles

A lot of the time, it's not the speedometer at all. It's one of the two speed sensors. I've had it happen to me with a Sebring convertible that had the same basic drive train as a PT.

The first thing to do is check the plugs on the speed sensors. For an automatic, they are on the front of the transmission beneath the battery tray. Make sure the plugs are clean and fully pushed on. From there follow the leads up as far as you can looked for damage to the wiring.

If no joy, you might consider changing out the speed sensors. The reason is that the next step after this will be much harder. So for me, I'd likely just grab a pair from a salvage yard for a couple of bucks each. These fit most PT Cruiser and a lot of other Mopar models for about two decades.

If no joy, the next thing to check is the connection of the gauge cluster to the dash. On the 1st Gen PT's (2001 thru 2005) this was badly designed. If the bolts that hold the cluster get a little loose, it can partially lose contact. And the contacts themselves sometimes tend to corrode. If me, I'd pull the cluster bezel, pull the cluster and clean the contacts on both the cluster and dash. The contacts in the dash are made into the plastic substructure of the dash itself. It's just a poor design. And as a I said, this is harder than swapping out the sensors.

If no joy, my next move would be to swap out the cluster. Salvage yards are full of PT Cruisers. You will want one from another 2001 thru 2005 model that has the same tranny type (auto or manual) as yours. It's the same with ABS or non-ABS. Get one that matches what you have now. The silver-faced ones from turbo PT's will not work right. I did a thread on that about four years ago.

There may be some additional diagnostics for this in the service manual. If you don't have a copy you can download one from my Google Driver at this link:

https://drive.google.com/file/d/0B9C...ew?usp=sharing

As a disclaimer, I just came for the dentist this afternoon and I'm well medicated at the moment. Beyond this, it should be noted that while I am an ASE Certified Master Automotive Tech and an excellent lover, I primarily work as a Safety Engineer among other things and I haven't worked as a professional mechanic since I was young strapping lad with long sexy flowing hair before college. And even then, I mainly worked on big trucks and heavy equipment. Nowadays, I enjoy working on these funny looking little cars for fun and relaxation. And I help others when I can.
chuzz likes this.
__________________

Last edited by Handy_Cruiser; 27 Feb 2019 at 07:45 pm.
Reply With Quote
  #3 (permalink)  
Old 27 Feb 2019, 09:50 pm
Fresh Cruiser
 
Join Date: Jan 2008
Posts: 24
Default Re: Speedometer troubles

Thanks for your reply. Guess I'll have to take it back to the garage. If you were closer, I'd hire you. (Good luck with your teeth!)
Reply With Quote
  #4 (permalink)  
Old 27 Feb 2019, 10:14 pm
rckstein's Avatar
Banned
 
Join Date: Dec 2010
Location: Texas
Posts: 15,518
Default Re: Speedometer troubles

Quote:
Originally Posted by Gabriella View Post
Thanks for your reply. Guess I'll have to take it back to the garage. If you were closer, I'd hire you. (Good luck with your teeth!)
Quote:
Originally Posted by Handy_Cruiser View Post

As a disclaimer, I just came for the dentist this afternoon and I'm well medicated at the moment. Beyond this, it should be noted that while I am an ASE Certified Master Automotive Tech and an excellent lover, I primarily work as a Safety Engineer among other things and I haven't worked as a professional mechanic since I was young strapping lad with long sexy flowing hair before college. And even then, I mainly worked on big trucks and heavy equipment. Nowadays, I enjoy working on these funny looking little cars for fun and relaxation. And I help others when I can.
I hope not because of this
Handy_Cruiser likes this.
Reply With Quote
  #5 (permalink)  
Old 28 Feb 2019, 04:26 am
RickinPA's Avatar
Cool Cruiser
 
Join Date: Jun 2014
Location: southeastern PA
Posts: 264
Default Re: Speedometer troubles

Is your PT a manual or automatic transmission?

I had an experience with my daughter's Neon and learned a few things about how the speedometer works these days (they're not like the old cable driven speedometers).

As Handy_Cruiser pointed out, the signal for the speedometer comes from the output speed sensor. He provides a good link to the service manual, the output speed sensor (automatic transmission) is shown on page 21-276 of the manual (page 1,658 of the PDF). The manual transmission speed sensor is a little different, it's shown on page 21-149 of the manual (page 1,531 of the PDF).

In my daughter's Neon (automatic transmission), the speedometer stopped working, warning lights went on and the transmission wouldn't shift out of first. Different from your problem, that's why I didn't reply before. But let's look at the output speed sensor.

It's some sort of magnetic inductive device. It sends a signal to the car's computer giving the computer the car's speed. From there, the computer tells the transmission what the car's speed is and also sends the processed signal to the speedometer to display the speed. The computer probably does other things with the signal, but I don't know what.

When I pulled the output speed sensor out of my daughter's Neon (~100k miles) it had an accumulation of ferrous particles on it due to it being magnetic. I cleaned them off. I also tried a new speed sensor. Neither corrected the problem. I noticed the one wire had some "stretch" at the contact (an internal wire break). I fixed the wire at the connector and that corrected her problem.

If your PT is an automatic transmission, I suspect output speed sensor problems would also affect the shifting.

However, if your PT is a manual transmission, perhaps the output speed sensor is the problem.

And now I know where the speed sensor is on my manual transmission PT.

Good luck with your problem.
Handy_Cruiser likes this.
Reply With Quote
  #6 (permalink)  
Old 28 Feb 2019, 10:31 am
Fresh Cruiser
 
Join Date: Jan 2008
Posts: 24
Default Re: Speedometer troubles

It's an automatic. Thanks for your reply. Once I get it fixed, I'll let everyone know what the problem was.
Reply With Quote
  #7 (permalink)  
Old 01 Mar 2019, 12:26 pm
Fresh Cruiser
 
Join Date: Jan 2008
Posts: 24
Default Re: Speedometer troubles

They're saying they've traced it back to the instrument cluster and I need another one. Problem is, they quit making them 8 years ago. They did find one used and I guess I have no choice. Is it a big deal replacing it? $391 seems like a lot, especially since it's a used part.


And what about the odometer? Will another cluster change the mileage? I've only got 76K miles on this 2002 and I don't want some huge number of miles showing.

Last edited by Gabriella; 01 Mar 2019 at 12:33 pm.
Reply With Quote
  #8 (permalink)  
Old 01 Mar 2019, 02:34 pm
Handy_Cruiser's Avatar
Obsessed Cruiser
 
Join Date: Oct 2013
Location: Arkansas
Posts: 10,094
Default Re: Speedometer troubles

Salvage yards are full of these. You can even buy one eBay for much less than that. Just chose one that has miles on the odometer that are similar to yours. It looks like the average price on eBay is between $35 and $45. That includes shipping. Here's a link:

https://www.ebay.com/sch/i.html?_fro...uster&_sacat=0
__________________

Last edited by Handy_Cruiser; 01 Mar 2019 at 02:38 pm.
Reply With Quote
  #9 (permalink)  
Old 01 Mar 2019, 02:44 pm
Young Cruiser
 
Join Date: Aug 2007
Posts: 73
Default Re: Speedometer troubles

The mileage is stored in the PCM and in the instrument cluster. The cluster will retain the mileage from the vehicle that it was pulled out of. The shop installing the cluster should be able to update the mileage as long as they have the scan tool to do it. if they can't do that for you then they should get a cluster from someone who can program the cluster mileage before it's installed. Dealer will probably charge an hour of labor to do it for you with the cluster installed.
Reply With Quote
  #10 (permalink)  
Old 01 Mar 2019, 05:01 pm
Fresh Cruiser
 
Join Date: Jan 2008
Posts: 24
Default Re: Speedometer troubles

Quote:
Originally Posted by Handy_Cruiser View Post
Salvage yards are full of these. You can even buy one eBay for much less than that. Just chose one that has miles on the odometer that are similar to yours. It looks like the average price on eBay is between $35 and $45. That includes shipping. Here's a link:

https://www.ebay.com/sch/i.html?_fro...uster&_sacat=0
Yeah, I saw the prices online. Just figured I must be paying more for labor than the part. I'd need a taxi and a mechanic to be able to get one from a salvage yard. Wish I had the cash to buy a whole new car...though I would buy a new PT.....IF they still made them.
Reply With Quote
Reply


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
pt troubles 05ptgirl Tech & Performance Forum 4 21 Jul 2012 12:23 pm
IAC troubles rob342 General PT Cruiser Discussions 1 16 Jun 2012 01:55 pm
06 troubles Jocko Tech & Performance Forum 4 26 Apr 2012 02:02 pm
Car Troubles PTCMIAH62 General PT Cruiser Discussions 9 07 Sep 2010 11:00 am
New guy... MBC troubles SRT Turbo Performance 3 02 Apr 2010 10:40 am


All times are GMT -5. The time now is 04:29 am.




Powered by vBulletin® Version 3.8.2
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
LinkBacks Enabled by vBSEO 3.6.0 PL2 © 2011, Crawlability, Inc.
vB.Sponsors