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-   -   no speedometer in my 94 chevy exdt. cab. HELP! (https://67-72chevytrucks.com/vboard/showthread.php?t=653545)

youngblood78 12-21-2014 12:30 AM

no speedometer in my 94 chevy exdt. cab. HELP!
 
Hey yall im new on this page here I have a 94 chevy ext. cab 4x4 with a manual tranny and I have no speedometer reading. every now and then it will bounce from 0 to close to the speed im doing then just falls and won't read I just got the truck today and would like to get it on the road daily driving asap ive read other places on wjat it could be vss. drac. But frankly im not tech. Savy so any imput from you guys would be greatly appreciated. Thank you.

rustymarco 12-21-2014 01:40 AM

Re: no speedometer in my 94 chevy exdt. cab. HELP!
 
change the speed sensor in the tail of the transfer just follow the wires, you not need to be a tech guy just take your tools and change it like a spark plug nothing go to exploit

ChevyTech 12-21-2014 05:04 PM

Re: no speedometer in my 94 chevy exdt. cab. HELP!
 
Speedo in-op

Here are some steps to see where the problems is.

Check and see if a trouble 24 is stored in the computer. If there is no speed signal getting to the computer it should have stored this code. Let me know if you need instruction on checking for a code.

Is the brake light on the instrument panel on?

RWAL was standard equipment starting in 1988 on full size trucks. RWAL stands for REAR WHEEL ANTILOCK. If the is no speed signal getting to the RWAL module, the RWAL system should set a trouble code and turn on the Brake light on the instrument panel.

If it has 4 wheel ABS that system will also set a code if there is a problem will the vehicle speed signal.

If there are no computer codes or anti-lock brake codes, then the problem is most likely inside the instrument panel.

If it has cruse control see if it works.

Here is a thread where it ended up being an ignition switch failure, but his vehicle had multiple problems.
http://67-72chevytrucks.com/vboard/s...d.php?t=365875

Mr_Rich 12-21-2014 05:22 PM

Re: no speedometer in my 94 chevy exdt. cab. HELP!
 
The speedo in my '89 intermittently drops and seems to do this more often when it's cold. I thought it was the speedo module and bought a NOS module off Ebay. I swapped it out and the problem still exists. I've determined it's an intermittent open on the gauge cluster circuit board. I'll eventually pull it out and re-solder the connections. For now I just bang on the gauge cluster with a knuckle and it starts working again. I catch the problem every time I hear the engine change tone since I don't stare constantly at the speedo.
What I wish is that there was a plug adapter to convert the 88-91 plug to the 92 and later plug so the later gauge cluster would fit the earlier trucks. I'm not ready to cut in to my wiring harness for a long time...

ChevyTech 12-21-2014 05:46 PM

Re: no speedometer in my 94 chevy exdt. cab. HELP!
 
Quote:

Originally Posted by Mr_Rich (Post 6966192)
The speedo in my '89 intermittently drops and seems to do this more often when it's cold. I thought it was the speedo module and bought a NOS module off Ebay. I swapped it out and the problem still exists. I've determined it's an intermittent open on the gauge cluster circuit board. I'll eventually pull it out and re-solder the connections. For now I just bang on the gauge cluster with a knuckle and it starts working again. I catch the problem every time I hear the engine change tone since I don't stare constantly at the speedo.
What I wish is that there was a plug adapter to convert the 88-91 plug to the 92 and later plug so the later gauge cluster would fit the earlier trucks. I'm not ready to cut in to my wiring harness for a long time...

This style of dash board has problems with the connection at the instrument panel. When hitting the dash helps, often cleaning the the connector will help.

There are varying opinions on the best practice for resolving the connection issue.

My suggestion is to be gentle when cleaning the connections.
Don't use a wire brush or rough sand paper on the connections.
I use a liquid cleaner & lube that protects the connection from air. This product is not longer available for retail purchase as far as I know.

youngblood78 12-22-2014 01:08 AM

Re: no speedometer in my 94 chevy exdt. cab. HELP!
 
Omk I think I have a common problem from what yall tell me . No it has not showed any check engine lights but I took it out on the back roads tonight and yes the park break light did come on not becuz I forgot the break havmt used it lol but the speedo did work for just a few seconds and read about right but then just started going crazy would read higher with rpms of motor pop the gas revs up speedo goes up and falls...

youngblood78 12-22-2014 01:17 AM

Re: no speedometer in my 94 chevy exdt. cab. HELP!
 
If its any count my water temp guage works half the time but all the others are fine

ChevyTech 12-22-2014 10:40 AM

Re: no speedometer in my 94 chevy exdt. cab. HELP!
 
If the park brake light came on, read the trouble stored in the Anti-lock system.

Here is a thread that will help.
http://67-72chevytrucks.com/vboard/s...d.php?t=399153

rustymarco 12-22-2014 03:07 PM

Re: no speedometer in my 94 chevy exdt. cab. HELP!
 
ground problem maybe ,check all the grounds

youngblood78 12-27-2014 10:15 PM

Re: no speedometer in my 94 chevy exdt. cab. HELP!
 
May have found my problem wires to the speed sensor on the back of the case were rubed bare from the front drive shaft flange going to get a new wire plug and all tie it up hope that fixes it... but while I was under the truck thought I would fix the vibrations I think comeing from a bad u joint and ran in to a delay pulled the yoke out of the case and lost some fluid not sure what gose back in it atf? Or gear oil its a nv 4500/np241 combo

ChevyTech 12-27-2014 10:59 PM

Re: no speedometer in my 94 chevy exdt. cab. HELP!
 
Rubbed bare VSS wires will definitely cause the problems your truck has.

New Venture Gear 4500 (5 speed) manual– Synthetic 75W-90,API GL-4 gear lube, P/N 12345871


New Process 241, 231 and 233 - Dexron II automatic transmission fluid - Old number P/N 1051855, new number P/N 12345881

youngblood78 12-27-2014 11:17 PM

Re: no speedometer in my 94 chevy exdt. cab. HELP!
 
Thanks chevy tech your knowledge is awesome
I asked about the case fluid because when I pulled the yoke out it looked like gear oil real thick consistency but red color

ChevyTech 12-27-2014 11:28 PM

Re: no speedometer in my 94 chevy exdt. cab. HELP!
 
You're welcome!

ATF is not thick so someone could have put another product in your transfer-case, maybe to help control leakage. Or maybe it is a mix of fluids.

youngblood78 01-07-2015 10:42 PM

Re: no speedometer in my 94 chevy exdt. cab. HELP!
 
Mixing the tcase fluid shouldnt hurt it though right?

ChevyTech 01-08-2015 11:46 AM

Re: no speedometer in my 94 chevy exdt. cab. HELP!
 
Using the wrong fluid can do damage.

This is even more of a concern in the Manual 5 speed transmissions. Especially the 5LM60, HM290, HG290,NV350,Getrag


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