Jump to content
millco

Speedo Not Working? . . . Any Ideas?

Recommended Posts

I hooked up the speed sensor on the transmission day before yesterday. I was all excited because the speedo started working and even seems to be accurate (I would think it would be wrong because the parts truck has 4.10 gears and this truck has 3.54's . . . . Unless it was 'wrong' in the parts truck . . . )

Anyway, after we had driven for a few miles and were almost at our destination, I realized that the odometer and trip weren't registering anything. I had the instrument cluster apart cleaning it and it looked fine. . . .

I do have to ask if there is another input for the 'distance' part of the speedo? (I do know that the rear axle ABS sensor is not hooked up . . . . ) (YET!)

Share this post


Link to post
Share on other sites

Ok, after conversing with a few people and thinking about it; the instruments should only get input from the speed or distance sensor to make the speedo work.

I changed out the cluster with another and now it registers miles!! As far off as the speedo is though I wonder if the odometer is anywhere near reality . . . . I can't believe the difference in the instrument clusters. The oil gauge and temp gauge on this one is way different than the first one I had in there. And of course the needle is broken off this speedo . . . . (I wonder if that is why it is reading so slow? Because it is 'starting' from a much lower speed than if it could rest against the stop?)

I'll keep playing around and see what I can come up with.

Share this post


Link to post
Share on other sites

I believe the instrument in the dash will all be the same no matter what tire / gear ratio combo different trucks come with. To compensate for this, you change out the drive gear on the speed sensor in the transmission.

I'm not having much luck finding a working one. I will search the internet and see what I come up with. I had changed it out with another that I thought had a good transistor (I believe the transistor blows in the circuit board but I still have to 'prove' that theory....) but it doesn't register miles either :ow:

At least I figured out why the last speedo was so far off: Someone had broken the pointer needle and then tried to glue it back on. The glue they used didn't work and the needle was basically moving pretty freely to where ever it wanted! There is no 'parking post' in there for the needle but this needle was at rest at about -30 MPH so when I got to where it reads 20 MPH I was actually at about 50!!!

Anyway, I took pics as I 'adjusted' the miles back to what I needed for this truck and plan on doing a write up on all I find. It really isn't too hard to do a bit of the work on these instruments, but it would be nice to know what I was doing! So, whatever I learn I will share with you all.

How many of you have had your 1st gen odometer or speedometer stop reading? (Please specify which or if both have stopped.)

Share this post


Link to post
Share on other sites

i had one on a 1gen stop [odometer]. it may be a bad idea to click trip odo when the rig is moving. just from a therorey from anothe rsource. mine was one of many 1 gen's i have had and [knock on wood] the only one with a bad odo. [speedo stil working] my 600,000 miler is stil working......... :ok:

Share this post


Link to post
Share on other sites

That is good to hear!! I have heard from people that these seem to stop working. When I got mine apart I saw that it was made by VDO. They make good gauges so hopefully these are not problematic. I got one from a friend and it didn't work either. The one that did work (with the wrong speedo) was out of a parts truck. I thought I would be sneaky and just remove the working odometer from this gauge and put it on my gauge since it's speedo works.

Well, after having to take it apart another time (I have lost count on how many times this cluster has been in and out of the truck and how many times I took it apart . . . . :wall: ) I got it working!!! This last time I had to take it back apart because the gears must have not been engaged correctly and kept it from registering any miles. I'm a lot happier that it works now!! Hopefully it is fairly accurate . . . Now I can get an idea of what kind of fuel mileage this old girl can give me!!

If I can figure out what broke on the original odometer then maybe I can help others fix theirs!! It's at least worth a shot if it turns out to be an easy fix!

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Upcoming Events

    No upcoming events found
  • Recently Browsing

    No registered users viewing this page.

×