Speedo Stuck


isaakgt

GT Owner
Mark II Lifetime
Dec 20, 2005
691
Wilder, Idaho
I have what would be considered a high mileage GT and have had absolutely no issues with the car since I purchased it in '06. On Saturday I drove the car to a local warbird show and had the speedo stick at 40mph. It will fluctuate about 2mph at speed and stays at 40 when the car is off. When I got home I disconnected the ground for about 30 min to see if the system needed to reset but nothing changed. Drove the car today (approx. 80mi.) with no change. The battery is original, works great and has been maintained with a 'Battery Tender' float charger. Has anyone had a simular issue? Where should I start? Thanks in advance, Tony :usa
 
Aug 25, 2006
4,436
I have what would be considered a high mileage GT and have had absolutely no issues with the car since I purchased it in '06. On Saturday I drove the car to a local warbird show and had the speedo stick at 40mph. It will fluctuate about 2mph at speed and stays at 40 when the car is off. When I got home I disconnected the ground for about 30 min to see if the system needed to reset but nothing changed. Drove the car today (approx. 80mi.) with no change. The battery is original, works great and has been maintained with a 'Battery Tender' float charger. Has anyone had a simular issue? Where should I start? Thanks in advance, Tony :usa

Sadly yes; I replaced one not long ago for the same reason.

I do not think that you have to look any further than a new speedometer.

Takes care

Shadowman
 

thegtguy

*Supporting Vendor* GT Owner
Apr 20, 2006
546
MI
Speedo

I would try the speed sensor first, its cheaper and easier. We just had one of those go bad too. This car had about 12k miles on it.
 

mardyn

GT Owner
Dec 20, 2005
490
Beautiful East Texas
Did the folks at Hollywood Speedo have any luck repairing the GT units yet? (mine is still inoperable as well)

mardyn
 
Aug 25, 2006
4,436
I would try the speed sensor first, its cheaper and easier. We just had one of those go bad too. This car had about 12k miles on it.

Hi thegtguy

As have I however with the needle stuck it is not a sensor issue because the sensor is a very simple magentic pulse generator that sends a signal but does not reset the speedometer.

Takes care

Shadowman
 
Aug 25, 2006
4,436
Did the folks at Hollywood Speedo have any luck repairing the GT units yet? (mine is still inoperable as well)

mardyn


mardyn

Kevin knows that the IC is the failed piece within and at some point in time is prepared to attempt to integrate a VDO unit within the OEM shell however to date this has not happened.

All the best

Shadowman
 

thegtguy

*Supporting Vendor* GT Owner
Apr 20, 2006
546
MI
Speedo

Hi thegtguy

As have I however with the needle stuck it is not a sensor issue because the sensor is a very simple magentic pulse generator that sends a signal but does not reset the speedometer.

Takes care

Shadowman



Just throwing an option out there and sharing experiences. Ours was stuck too for whatever reason and the owner put in 2 speedo's himself, then brought the car to us. I checked the OSS (Output shaft sensor) input through our scan tool and it wasn't reading. New sensor and now functioning speedo. I will say that this is not the norm as most of the time it has been the faulty gauges.
 

Empty Pockets

ex-GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Oct 18, 2006
1,361
Washington State
Tony:

Based on Bill & Rich's experiences, if it were me, since a speedo is $3,000(!!!), I'd buy a 75 cent (relatively speaking!) sensor 1st and p-r-a-y that your situation is a rare case like Rich just mentioned.

'Worth the gamble. Maybe "Murphy" is on vacation...?
 
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isaakgt

GT Owner
Mark II Lifetime
Dec 20, 2005
691
Wilder, Idaho
I changed the 15.00 sensor and it wasn't the prob, but the best place to start. The new speedo is on the way and at a reasonable cost. I hope nobody has had to pay 3 g's for a speedo that may need replacement every 10-15k miles. Thanks again for the help, much appreciated. :thumbsup
 
Last edited:
Aug 25, 2006
4,436
I changed the 15.00 sensor and it wasn't the prob, but the best place to start. The new speedo is on the way and at a reasonable cost. I hope nobody has had to pay 3 g's for a speedo that may need replacement every 10-15k miles. Thanks again for the help, much appreciated. :thumbsup

Thank you for the update

Takes care

Shadowman
 

Fast Freddy

GPS'D 225 MPH
Mark II Lifetime
Aug 5, 2005
2,685
Avondale, Arizona
my speedo is stuck on 217 mph :willy

a whipple supercharger should get it to move a lil HIGHER though :lol
 

isaakgt

GT Owner
Mark II Lifetime
Dec 20, 2005
691
Wilder, Idaho
my speedo is stuck on 217 mph :willy

a whipple supercharger should get it to move a lil HIGHER though :lol



It is a bit embarrassing to be stuck at 40mph. :ack
 

Empty Pockets

ex-GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Oct 18, 2006
1,361
Washington State
It is a bit embarrassing to be stuck at 40mph. :ack


Before Clinton even has a CHANCE to say it: "That's not as embarrassing as E.P.'s speedo being permanently stuck on zero."
 

BlackICE

GT Owner
Nov 2, 2005
1,416
SF Bay Area in California
You read my mind! :lol
 

Empty Pockets

ex-GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Oct 18, 2006
1,361
Washington State
You read my mind! :lol


'Not too much of a challenge at this point!!! :rofl:rofl:rofl :cheers
 

isaakgt

GT Owner
Mark II Lifetime
Dec 20, 2005
691
Wilder, Idaho
Before Clinton even has a CHANCE to say it: "That's not as embarrassing as E.P.'s speedo being permanently stuck on zero."


EP, I failed to mention that the speedo stuck while I was backing out of the garage.:biggrin I did follow Shadowman's precise instructions from a previous thread on how to remove the instrument cluster. I was very cautious and used a lot of blue tape & towels as recommended. The trick is fishing the harness through a tight slot while you gently pull the guage panel from the dash. The whole process took me about 2 1/2 hrs to complete, taking my time. Everything is now working well now. Thanks again. :thumbsup
 
Aug 25, 2006
4,436
EP, I failed to mention that the speedo stuck while I was backing out of the garage.:biggrin I did follow Shadowman's precise instructions from a previous thread on how to remove the instrument cluster. I was very cautious and used a lot of blue tape & towels as recommended. The trick is fishing the harness through a tight slot while you gently pull the guage panel from the dash. The whole process took me about 2 1/2 hrs to complete, taking my time. Everything is now working well now. Thanks again. :thumbsup

You did good!!!! and "thank you" for the update and the kind words.

If ever I can assist just let me know

Takes care

Shadowman