hi fellas
My speedo is stuck at the far end off its travel. I changed some fuses under the bonnet recently as the interior light had blown. After this the speedo doesnt work and just sits at the far end at around 280km/hr. I 've checked all the fuses, checked all the connections into the dash but nothing has helped. The car knows the speed its doing as the speed alert can be adjusted so i assume the VSS is working fine. From my reading on the forum when the speedo's stop working they sit at 0 km/hr. Havent come across this where its stuck at the far end
any idea's
cheers

Hmm.....have you tried a simple disconnect of the battery?

Had an issue with my old verada wagon, for some reason after a stereo install the rear wiper started by itself and wouldnt stop....simply disconnecting and reconnecting the battery fixed the issue

Point is sometimes the wierdest things can have a simple fix

Looking in the TJ/TH manual (which might be different in this area) the speedo and tacho share power and earth, so if your tacho is fine you should be able to eliminate those circuits. The only other wire to the speedo is the signal wire from the speed sensor, but if your vehicle speed alert is working it would seem to be working. Does it return to 0 with the key out and/or battery disconnected? If not, and it stays at 280, my guess is your speedo is cactus (or maybe stuck, possibly a Fonzie-style whack is called for? :)

Ah, this happened to me recently. Battery died and when the new one was put in there must have been some kind of spike, anyhow the needle swung so hard around it got jammed near the 6pm mark where the panel and front perspex are closer together.

Only solution is to remove cluster, remove perspex front and gently push needle back. It needs to be pushed a fair way before it will swing back to 0.

I checked it against my GPS and its spot on, so no lasting damage.

Thanks fella's
Things that haven't worked so far....
Violence
Swearing
Taking a vow of chastity
Seriously, have disconnected the battery- still not working
Jiggled connections on speedo jiggled connections on the VSS - still no worky
This weekend the cluster comes off

Sounds like you're on the right track, that's pretty much the standard workflow isn't it? :)

An analogue speedo (or any instrument for that matter) is simply an ampmeter. The circuitry will be Battery to Instrument Power Supply (probably 7v) to ampmeter (speedo) to a variable resistor (probably incorporated in the speedo connection at the gearbox) to earth. The faster you go, the lower the value of the variable resistor and hence more current going through the circuit. If you have a short circuit to earth somewhere after the speedo ie in the gearbox sensor or the wiring to it, it will look like max speed and the needle will go flat out. This may have been a momentary short, and the needle is stuck at full scale, or it could be one which is still there and causing the needle to swing out there.

If it stays at full scale when the power is off, the needle is stuck. Dismantle the instrument pod (be very careful with the printed circuit board at the back of the pod) and mechanically release the needle.

Have you considered that you are actually still travelling at 280 km/h relative to a 'something'? Did you get a visit from an alien perhaps? They have all sorts of electromagnetic energies. Who knows what else it could have done to your car. Perhaps to fix it you could speed your car up to 280 km/h and 'catch' the needle. When you slow down, the needle will show your speed normally.

An analogue speedo (or any instrument for that matter) is simply an ampmeter. The circuitry will be Battery to Instrument Power Supply (probably 7v) to ampmeter (speedo) to a variable resistor (probably incorporated in the speedo connection at the gearbox) to earth. The faster you go, the lower the value of the variable resistor and hence more current going through the circuit. If you have a short circuit to earth somewhere after the speedo ie in the gearbox sensor or the wiring to it, it will look like max speed and the needle will go flat out. This may have been a momentary short, and the needle is stuck at full scale, or it could be one which is still there and causing the needle to swing out there.

If it stays at full scale when the power is off, the needle is stuck. Dismantle the instrument pod (be very careful with the printed circuit board at the back of the pod) and mechanically release the needle.
No, i expect the speed sensor will be a pulse type sending a signal to the ECU, which would in turn control the instrument cluster display.

Thank you earthlings
3 hours of taking off the dash. The needle was stuck. It was stuck on the small lip at max speed and couldn't spring back. It must have been a short that happened when checking fuses, so let this be lesson to you carbon based life forms. Don't check your fuses with the accessories still on.
Live long and prosper

Don't forget to take a pic and upload to FB and tell everyone that you achieved a new high speed record on the way home from work today before you dismantle the cluster (cluster removal is easy as!)

thank you earthlings
3 hours of taking off the dash. The needle was stuck. It was stuck on the small lip at max speed and couldn't spring back. It must have been a short that happened when checking fuses, so let this be lesson to you carbon based life forms. Don't check your fuses with the accessories still on.
Live long and prosper
lol......

picture coming soon...

You at least for a while had the fastest accelerating third gen on the forums, 0-280 in the turn if a key, break neck speeds!

This thread is full of greatness.

Glad you fixed the problem!

sorry its a bit blurry but at 280 the old girl gets a bit shaky. :)
cant upolad pictures but have placed it in my album
cheers