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Topic Review (Newest First)
01-23-2014 10:22 AM
OverkillYJ Mine went from bouncing to either working or not working. Its about 50/50.
01-22-2014 10:27 PM
Tbuchle
jumpy Spedo

I to am having this problem. I have a 97 TJ. I will be checking all the this ASAP. The other day it started up in a 20mph school zone! Thanks for all the help in advance.
01-21-2014 11:23 AM
Lowrollin12 yea that was the first thing I did...
01-06-2014 04:35 PM
Big Sarge
Quote:
Originally Posted by Lowrollin12 View Post
I cant believe no one else has ever had this issue!!!! THIS SUCKS!!!!
so have you replaced the VSS with a new one?
01-06-2014 12:08 PM
Lowrollin12 I cant believe no one else has ever had this issue!!!! THIS SUCKS!!!!
12-27-2013 11:02 AM
Lowrollin12 Ok then, we have a different issue... FUN!
12-21-2013 07:08 AM
Big Sarge Yep that's what made mine so weird. That's also what made me go for the wiring harness.
12-20-2013 03:09 PM
Lowrollin12
Quote:
Originally Posted by Big Sarge View Post
i guess it was around 5 feet or so. It was just the length from the sensor to the PCM. Yeah I know it can be frustrating. I even disconnected my VSS and it still was going crazy. Had me stumped for a while as all wires seemed fine in the beginning.
You disconnected the speed sensor and still had the issue?

When I unplug mine it just reads zero.
12-12-2013 10:53 AM
Big Sarge
Quote:
Originally Posted by Lowrollin12 View Post
I appreciate your help...You know how frustrating this is! How much wire did you replace? and you did it on both ends? (sensor and PCM) I put my old gauge cluster in last night and same issue.
i guess it was around 5 feet or so. It was just the length from the sensor to the PCM. Yeah I know it can be frustrating. I even disconnected my VSS and it still was going crazy. Had me stumped for a while as all wires seemed fine in the beginning.
12-12-2013 08:52 AM
Lowrollin12
Quote:
Originally Posted by Big Sarge View Post
I replaced the capacitor (my brother did) and it had no affect on anything. Not sure what it's purpose is. My was definitely the VSS to PCM signal wire.
I appreciate your help...You know how frustrating this is!

How much wire did you replace? and you did it on both ends? (sensor and PCM)

I put my old gauge cluster in last night and same issue.
12-11-2013 08:24 PM
Digger84 You clarified all that previously and as I understand it replacing the one wire from the sensor to the PCM perminately solved your intermittent problem.

The question I had was did you think the bypassed wire was shorting to another wire or ground, or had a intermittent internal interruption. ( broken strands only sometimes making contact)
Or was picking some external signal noise due to lack of adequate shielding
12-11-2013 01:35 PM
Big Sarge I replaced the capacitor (my brother did) and it had no affect on anything. Not sure what it's purpose is. My was definitely the VSS to PCM signal wire.
12-11-2013 12:21 PM
Lowrollin12
Quote:
Originally Posted by Big Sarge View Post
yes that is what I did. I only cut the white/orange wire though. That is the signal wire so I started there. For me that was the fix. If it would not have worked I would have went for the other two as well.
What ever happened with the capacitor in the gauge cluster?

I have a second gauge cluster that I am going to swap to see what that does.

I also don't have brake lights and have no idea why...
12-09-2013 09:50 PM
OverkillYJ I have a late 95 YJ with a manufacture date of Dec 95. I have a lot of TJ parts. As for the speedometer system, it is TJ except for the computer and Gauges. Wiring is all the same. I am going to check continuity between the body grounds and my speedo sensor wire as well as the gauge cluster. I cant figure out why the hell it is still screwed up.
12-09-2013 09:12 PM
Big Sarge
Quote:
Originally Posted by Digger84 View Post
Did the diagnostic/test cluster function go thru all the normal sequence even when you had a problem( before you added a new wire)? Did you get a copy of the 98 FSM with wiring diagrams or do you still need one? After you cut and bypassed the old wire did you check it's resistance and verify it had neither a ground connection or any voltage relative to ground (after it was just a wire with two ends connected to nothing) as the issue was intermittent it might test normally but any abnormal results might help someone else decide if they needed to bypass that wire? That is of course assuming that you did not yank the old bypassed wire out of the harness. As I understand it your new wire is stuffed into the same harness as the old one so any induced noise would Likely still be the same suggesting the old wire had an intermittent contact with another wire in the bundle
I assume you are talking to the other guy and not me? (Helps to quote the message you are referencing). My speedo is alive and well and has been since I added the new wire. My test function on the cluster went through the test as a normal one would. That just test the cluster itself in which case mine was fine. The other guy has a YJ not a 98. Not sure his setup is the same but he thought it may be somewhat similar.
12-09-2013 08:49 PM
Digger84 Did the diagnostic/test cluster function go thru all the normal sequence even when you had a problem( before you added a new wire)?

Did you get a copy of the 98 FSM with wiring diagrams or do you still need one?

After you cut and bypassed the old wire did you check it's resistance and verify it had neither a ground connection or any voltage relative to ground (after it was just a wire with two ends connected to nothing) as the issue was intermittent it might test normally but any abnormal results might help someone else decide if they needed to bypass that wire?
That is of course assuming that you did not yank the old bypassed wire out of the harness.

As I understand it your new wire is stuffed into the same harness as the old one so any induced noise would Likely still be the same suggesting the old wire had an intermittent contact with another wire in the bundle
12-09-2013 06:58 PM
Big Sarge
Quote:
Originally Posted by Lowrollin12 View Post
So I am glad I finally found this because I have been pulling my hair out trying to fix this.... So what you are telling me is to cut the ends of the wire for the VSS at the sensor and the PCM and replace them? Sorry I just want to be sure, doesn't make any sense.
yes that is what I did. I only cut the white/orange wire though. That is the signal wire so I started there. For me that was the fix. If it would not have worked I would have went for the other two as well.
12-09-2013 06:52 PM
OverkillYJ Mine started acting up again after all this. Still haven't figured out out.
12-09-2013 05:30 PM
Lowrollin12 So I am glad I finally found this because I have been pulling my hair out trying to fix this.... So what you are telling me is to cut the ends of the wire for the VSS at the sensor and the PCM and replace them?

Sorry I just want to be sure, doesn't make any sense.
10-07-2013 09:19 AM
OverkillYJ Yeah I have a late model YJ. Manufacture date of Dec 95, so needless to say it has some TJ parts on it. What I am talking about is where the vss harness goes into the main harness that cuts over to the PCM. You may have just had wear on the one wire, I definitely have wear on other wires. I could have spliced it in at the PCM, but I didnt have to for that wire. What I am going to do next is pull the VSS/Reverse light harness out through the engine compartment and open the whole thing up to see what is frayed. I will replace anything worn and pull it back through and hook it up. If that doesn't resolve it 100% then the rest of the problem remains over at the CPS where it meets the VSS wires. The reason I am thinking it may be in that area is that when I start the Jeep the speedometer revs up for a second with the RPMs.
10-07-2013 07:53 AM
Big Sarge Is your Jeep not a YJ? Also not sure what you mean by coming into the main harness? I cut the wire at the VSS, cut same wire at the PCM, put new wire in (also in the black tube/protector) and re connected to both ends. Almost 4 months and have zero issues on mine.
10-07-2013 07:37 AM
OverkillYJ Just to help other people with this problem. I did replace the one wire mentioned in this thread, but only up to where it comes into the main wiring harness. I didnt replace it through the main wiring harness because I know the wire would not be worn there. I opened up the main harness and everything still looked brand new. So after replacing the wire you mentioned up to that point it has gotten quite a bit better, but it is still not solved. I am now 90% certain that at least one of the other wires is worn. I assume the VSS works on resistance and that one of the wires is slightly exposed from rubbing and is grounding out causing the speedo to act crazy. Once I solve it for good I will update again. I probably wont get to it for a week or so though.
09-20-2013 08:55 PM
OverkillYJ
Quote:
Originally Posted by Big Sarge View Post

I didn't pull the harness. Just cut the wire at both ends and added a new piece.
It's no big deal for me. I got a lift and want to put the wire inside the harness and tuck everything in tight. It makes sense that would be a cause. I removed the vacuum lines when I swapped in a axle on my passenger side, the wires must have been rubbing a bit from the extra space since I just slid the tubes out of the harness.
09-20-2013 08:23 PM
Big Sarge
Quote:
Originally Posted by OverkillYJ View Post
Awesome dude! I will be pulling the harness soon then and replacing that wire. I already have everything I need, now just need the time. After I do it I will try to remember to update this thread.
I didn't pull the harness. Just cut the wire at both ends and added a new piece.
09-20-2013 08:05 PM
OverkillYJ Awesome dude! I will be pulling the harness soon then and replacing that wire. I already have everything I need, now just need the time. After I do it I will try to remember to update this thread.
09-20-2013 06:18 PM
Big Sarge
Quote:
Originally Posted by OverkillYJ View Post
Did that fix your problem? I am going crazy. I already replaced the speedo, and have spent hours under my Jeep thinking it was the sensor, or sensor related. And what orange/white wire were you talking about? I know that may be a different color in mine since I have a different computer and cluster, but I can read wiring diagrams fine if I know what the wire is for.
Yep it fixed my problem. It's the speed sensor signal wire that runs from the speed sensor to the computer. May have to find schematics for your year and engine. Mine was white with an orange stripe. Good luck, it drove me crazy as well until I did that and got it fixed.
09-20-2013 05:31 PM
OverkillYJ Did that fix your problem? I am going crazy. I already replaced the speedo, and have spent hours under my Jeep thinking it was the sensor, or sensor related.

And what orange/white wire were you talking about? I know that may be a different color in mine since I have a different computer and cluster, but I can read wiring diagrams fine if I know what the wire is for.
06-24-2013 11:14 AM
Big Sarge Well it looks like I may have fixed the problem.


I cut the white with orange tracer wire near the PCM and near the VSS and just added in a new wire. Seems to have fixed the problem. Time wi tell I suppose.
05-31-2013 07:21 AM
Big Sarge 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
05-30-2013 05:58 PM
Big Sarge 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.
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