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-   -   Speedo gone crazy (http://www.wranglerforum.com/f210/speedo-gone-crazy-237400.html)

Big Sarge 04-24-2013 05:17 AM

Speedo gone crazy
 
On my way to work this morning, my speedometer just started going crazy. It bounces even while sitting at a stoplight from 0 to 100 mph. Any ideas?

Big Sarge 04-24-2013 06:19 AM

All other gauges are 100% normal.

Big Sarge 04-25-2013 12:16 PM

It seems to be getting more erratic as I'm unable to find a bad connection or anything. Nobody else has ever had this problem. Again it also does it just sitting still sometimes.

speelbider 04-25-2013 12:18 PM

Sounds like it might be the vss... it gets mounted on the end of the transfer case.

Dextreme 04-25-2013 12:25 PM

Mine does that about 1-2 times a week. Supposedly its just a loose connection behind the instrument panel. I should fix mine someday too.

Big Sarge 04-25-2013 12:35 PM

Quote:

Originally Posted by speelbider (Post 3681633)
Sounds like it might be the vss... it gets mounted on the end of the transfer case.

is that he piece that sits on top of the speedo gear where the wire connector plugs in?

speelbider 04-25-2013 12:47 PM

Exactly the piece.... I had the same issue... changed the vss... problem fixed

CoreyZ 04-25-2013 12:50 PM

Yeah, check the speedo gear. It might have broken or come loose. Its quick and easy to get to.

Big Sarge 04-25-2013 03:33 PM

Well I disconnected the cable going to the VSS and it is still jumping back and forth.

Big Sarge 04-29-2013 05:12 PM

Does anybody have the wiring schematic for the speedometer? Cleaned the connections under the good today and thought it fixed it. After driving a little bit it started acting up again. I feel certain it is just a wire connection but need the schematic to trace it down.

Big Sarge 05-15-2013 06:23 PM

Bringing this thread back to life in hopes of some additional help. I was able to get complete wiring schematics from online. I looked through all the wiring and everything seems good to go. However my speedo is still acting crazy. It has almost gotten to the point now that it seems to react to the accelerator even sitting still meaning, I can be sitting still, rev the engine, and the speedo will jump up. Sometimes it does it without even revving the engine. I'm lost at this point. As stated before I have even disconnected the VSS and it still does it. With it disconnected I racked up 15 miles on my 10 mile commute to work!! Any help is appreciated.

flflash 05-15-2013 06:41 PM

Thats normaly caused by a short across the printed circuit board on the back of the IPC. Has it been rained on lately?

Big Sarge 05-15-2013 06:48 PM

Quote:

Originally Posted by flflash (Post 3759253)
Thats normaly caused by a short across the printed circuit board on the back of the IPC. Has it been rained on lately?

Not sure what an IPC is?? I'm guessing instrument cluster? And if so then no the top has only been down once and it was after this problem started and it didn't rain that day.

flflash 05-15-2013 07:06 PM

Instrument panel cluster, if you feel comfortable pulling it out pull it out and look closely at the plug in the back. Was it fully inserted? ?s there any corrosion on it ( white to greenish powdery stuff ) the plugs on the back of the IPC are notorious about backing out or getting minor corrosion on them and causing issues. You can carefully and gently clean the connector and circuit board with electrical contact cleaner and see if it helps.

Big Sarge 05-15-2013 07:16 PM

1 Attachment(s)
Quote:

Originally Posted by flflash (Post 3759329)
Instrument panel cluster, if you feel comfortable pulling it out pull it out and look closely at the plug in the back. Was it fully inserted? ?s there any corrosion on it ( white to greenish powdery stuff ) the plugs on the back of the IPC are notorious about backing out or getting minor corrosion on them and causing issues. You can carefully and gently clean the connector and circuit board with electrical contact cleaner and see if it helps.

Yeah I came out and pulled it just to check after I was pretty sure that's what you meant. No corrosion or loose connections. I did take the white cover off the back of the IPC and there seems to be a capacitor in the bottom left corner (bottom right looking at it face down) closer to the fuel gauge area that appears to have gotten hot or something. Maybe that could be the problem? The speedo is the only gauge not working properly. All others function perfectly.

flflash 05-15-2013 07:34 PM

Unfortunatly it looks like you may have found the problem, last one I had sent off and repaired cost $320 and took a week to get back. You may be able to get a rebuilt exchange unit thru your local dealer for about that price or run thru the legal issue's of putting a used one in from another vehicle.

Big Sarge 05-15-2013 07:38 PM

Quote:

Originally Posted by flflash (Post 3759428)
Unfortunatly it looks like you may have found the problem, last one I had sent off and repaired cost $320 and took a week to get back. You may be able to get a rebuilt exchange unit thru your local dealer for about that price or run thru the legal issue's of putting a used one in from another vehicle.

Fortunately my brother is an electronics nerd, actually a computer programmer I just like to pick on him. Lol. I called him already and he said he can replace it for me no problem. I hope that fixes it. Not a big issue just drives me insane.

AC0QR 05-15-2013 10:34 PM

If that does not fix it, try changing your spark plugs. Seriously.

Similar thing happened to me. Turns out my plug gaps were way too wide, and the spark was sometimes jumping across the coil instead of the plug. This caused a surge up the control wires to the PCM, where the circuitry for the speedo and coil are close by.

flflash 05-16-2013 05:26 AM

Quote:

Originally Posted by Big Sarge (Post 3759442)
Fortunately my brother is an electronics nerd, actually a computer programmer I just like to pick on him. Lol. I called him already and he said he can replace it for me no problem. I hope that fixes it. Not a big issue just drives me insane.

Good deal! Hope it takes car of it.

Big Sarge 05-29-2013 05:35 PM

1 Attachment(s)
Well I got said capacitor changed a couple weekends ago and problem still was there. I have changed the plugs, wires, distributor cap and rotor button as well as coil. All needed replaced anyways so no big loss there. But the speedo continues to do its own thing. Uggghhh

Waiting to catch my neighbor and swap in his cluster to see if my cluster went bad from the leaky capacitor.

Big Sarge 05-30-2013 11:23 AM

Swapped in a known good instrument cluster and nothing changes!!!! Someone please help before I go crazy. LOL

mudmagnet63 05-30-2013 11:54 AM

Mine goes erratic sometimes. It will rock the house for a while then nothing for maybe a mile or 2 weeks. I just use duct tape.

Big Sarge 05-30-2013 12:03 PM

Quote:

Originally Posted by mudmagnet63 (Post 3808135)
Mine goes erratic sometimes. It will rock the house for a while then nothing for maybe a mile or 2 weeks. I just use duct tape.

By nothing you mean it just reads "0"?? If so your problem could be the VSS (vehicle speed sensor).

I'm looking for a proper fix though not just duct tape it. Lol thanks though I did get a good laugh out of that one.

mudmagnet63 05-30-2013 12:10 PM

Yeah Sarge I go from 0 to 90 in a flash. I hasn't done it in about a month so who knows. I feel for ya electrical gremlins suck

Big Sarge 05-30-2013 04:41 PM

Any evening readers have any input?

kshaws21 05-30-2013 05:07 PM

Quote:

Originally Posted by flflash (Post 3759428)
Unfortunatly it looks like you may have found the problem, last one I had sent off and repaired cost $320 and took a week to get back. You may be able to get a rebuilt exchange unit thru your local dealer for about that price or run thru the legal issue's of putting a used one in from another vehicle.

$320? Wow, there is a place www.myairbags.com that will totally rebuild most any cluster with NEW gauges and lights for $75 plus shipping and the turn around is 24 hrs from the time they get it. I know two people who have used them and their clusters are now as new.

Big Sarge 05-30-2013 05:49 PM

Just wish that was my problem. I have found a plethora of used clusters for $50-$75. After swapping one in today it's not my issue so I won't waste that money.

kshaws21 05-30-2013 05:54 PM

Quote:

Originally Posted by Big Sarge (Post 3809252)
Just wish that was my problem. I have found a plethora of used clusters for $50-$75. After swapping one in today it's not my issue so I won't waste that money.

Could be the connection the cluster plugs in to. Try spraying some contact cleaner in there. If there is buildup on those connections, even a good cluster still wouldn't make good contact.

Big Sarge 05-30-2013 05:58 PM

I can give it a shot but my connectors look very clean and are coated really good with dielectric grease. I won't completely rule it out (because I have no clue at this time) but it would be hard for me to comprehend it being isolated solely to the speedo. I do appreciate the insight though.

Big Sarge 05-31-2013 07:21 AM

Bumping for anybody else before I make my 4 hour drive today. Probably will need something to cover the cluster to avoid smashing it while having to watch the crazy speedo that long. Lol


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