Tachometer Stopped Working


richardhead

GT Owner
Sep 19, 2006
169
Three Thoughts

(1) Again, does anyone have any thoughts as to whether or not the S/C Mustang guage control unit will drive the GT gauges?

(2) with regard to the folks where there have been guage failures: did you notice any thunderstorms or lightening strikes around the time your guages went out. If, for some reason, the control units are not properly "shielded" and grounded, an electrical storm EMP (ElectroMagnetic Pulse) from lightening could induce high voltage in the units and blow circuitry. Picking up this pulse is very easy where moving coil units drive mechanical guage needles. A charge can be induced in the coil and travel back to the electronic drive unit, or if any circuitry is in the guage it can also be damaged. Besides lightening, there are also other sources for this type of induced voltage spiking.

Perhaps DataDale can check with the engineers regarding the "hardening" or shielding of the control units and the guages to avoid this problem? If the control module is subject to picking up these pulses, it might be able to be shielded and grounded to prevent picking up this interference.

(3) Also, with regard to another source of EMP induced voltage spikes, is it possible high voltage is being picked up through unshielded wiring running close to the ignition coils? Or perhaps the alternator coils and charging system?

Just a few more thoughts for consideration. I know AnalogDesigner might have some additional input to this theory. Jay, if you are up to the task?



Hi Dale

I sent you an email

Thank you on behalf of "all"

Shadowman
 
Last edited:
Aug 25, 2006
4,436
(1) Again, does anyone have any thoughts as to whether or not the S/C Mustang guage control unit will drive the GT gauges?

(2) with regard to the folks where there have been guage failures: did you notice any thunderstorms or lightening strikes around the time your guages went out. If, for some reason, the control units are not properly "shielded" and grounded, an electrical storm EMP (ElectroMagnetic Pulse) from lightening could induce high voltage in the units and blow circuitry. Picking up this pulse is very easy where moving coil units drive mechanical guage needles. A charge can be induced in the coil and travel back to the electronic drive unit, or if any circuitry is in the guage it can also be damaged. Besides lightening, there are also other sources for this type of induced voltage spiking.

Perhaps DataDale can check with the engineers regarding the "hardening" or shielding of the control units and the guages to avoid this problem? If the control module is subject to picking up these pulses, it might be able to be shielded and grounded to prevent picking up this interference.

(3) Also, with regard to another source of EMP induced voltage spikes, is it possible high voltage is being picked up through unshielded wiring running close to the ignition coils? Or perhaps the alternator coils and charging system?

Just a few more thoughts for consideration. I know AnalogDesigner might have some additional input to this theory. Jay, if you are up to the task?

UPDATE

I had a couple wonderful chats with DataDale today

Takes care

Shadowman
 

NorthwoodGT

GT Owner
Jun 12, 2009
1,215
Michigan
At $1300, isnt it still 3 times the cost at this time last year. I think it is still rediculously overpriced specifically because of the high failure rate. Somehow we should decide what is palitable and pass that back to Ford. Maybe around $800???

Proving once again, no matter what the cost is, people are still going to complain!
 

richardhead

GT Owner
Sep 19, 2006
169
Another Thought for Shadowman

On my Corvettes, I have had occasion to see a bad (usually corroded, but sometimes broken wire) ground cause an reverse current flow through some circuits. In a lot of cases the clue was the lights dimming. Essentially, the power draw found a route through another circuit when it couldn't complete through its own. And what we determined happened was current flowed in reverse from what the original circuit was designed to do.

On light bulbs, having the polarity reversed doesn't matter...but electronics that don't have reverse polarity protection can be a problem, and having any reversed polarity will sometimes burn those systems out. Some electronics manufacturers will warn of this possibility if you hook up their product wrong, or inadvertently cross power it when an adjunct unit fails that has the polarity hooked up differently. I know this is the case with some trailer braking electronics and the backup circuits for the trailer break-away switches. Both the breakaway battery and the car battery must be connected with the same polarity or, under certain circumstances, the in-car brake control unit can be damaged when the break-away switch activates.

So, there is also the possibility of some sort of reverse polarity current damaging these guage control units and gauges. If it is determined this is the case, I believe an inexpensive diode controlled directional current flow protector could be installed in the guage control circuitry.

Just another thought for you, Bill...



UPDATE

I had a couple wonderful chats with DataDale today

Takes care

Shadowman
 

GT35065

GT Owner
Mark II Lifetime
Hope somebody can figure something out so I can fix my tach and temp guage soon. My tech at Ford dealer is stumped, partly because he hasn't been able to get satisfactory response back from the tech people at Ford. Usually they have been super helpful, but my guess is they are stumped for the moment too.
 

junior

GT Owner
Mar 9, 2007
1,151
So Cal
Could it be that Ford may not have a "good" fix ? Has someone contacted any of the "suits" at Ford ? And how about Britospeed, do they make other gages than the boost gage for the F-GT ?
 

LONEWATTE

GT Owner
Dec 7, 2006
14
West Palm Beach,Fl
mine quit too only 3200 miles on it.... verdict: replaced. Now the volt meter has stopped working, and I do keep a charger on the battery when not in use!
 

GT35065

GT Owner
Mark II Lifetime
Lonnewatte, sorry you had to join this not so exclusive club of guage failures.
 

hollywoodstunts

GT Owner
Apr 25, 2009
167
Venice, CA
Proving once again, no matter what the cost is, people are still going to complain!

When, or if any of you have your tach replaced, may I suggest you resist the temptation to ask for the tach back. I understand the fact that it's a limited production item, and not made in the numbers that say an Escort speedo is, but I've seen clocks at Kmart for $4.99 that have a more quality feel. All I'm saying is I was looking forward to feeling what two weeks ago was a $2700 tack in my hands. I was expecting to be in awe of the craftsmanship. Instead I was left uninspired.

Contrary to one posting, I don't feel the end user should set prices.

BUT, if a part, in this case the gauges, have an abnormally high failure rate, then the manufacturer should step in an address the issue. I appreciate the acknowledgement in the 50% price reduction-to me, it feels like a way to appease your customers without acknowledging a problem. But failures continue. And they will continue.

Should I buy a second $1300 tach in case they go back up 50%?

Some sort of closure would be great. Hey, I'm glad while my GT was in the shop, the repair I was looking at went from near $4000 to a little over $2000, but I don't feel I have solved my problem. Only put a band aid on a wound that could reopen at any time.
:confused
 

ViperJoe

GT Owner
Mark II Lifetime
Aug 17, 2006
1,305
Washington Crossing, PA
..... but I don't feel I have solved my problem. Only put a band aid on a wound that could reopen at any time.
..... and that is the really disconcerting part of this issue!

.
 

Bill Briley

GT Owner
Aug 9, 2005
212
Valley Forge PA.
..... and that is the really disconcerting part of this issue!

.

I havent' seen the inside of one of these gauges. But, if I have the misfortune, I will try and put an analoge "Gut" replacement behind the stock face plate. This will eliminate the Module and the stock electrical harness.
I would use VDO or another competitor of Autometer.
Anyone want to "lend" me a broken tach/gauge?
I don't think I trust Ford to help. Maybe Toyota?
 

GT35065

GT Owner
Mark II Lifetime
Ford may help, just needs to be brought to the right persons attention. I think there are people working on this (he says hopefully). This has got to be a serious design flaw. Knowing I've easily spent over $250,000 on Ford products over the last few years, I'm hoping for help.
 

hollywoodstunts

GT Owner
Apr 25, 2009
167
Venice, CA
I havent' seen the inside of one of these gauges. But, if I have the misfortune, I will try and put an analoge "Gut" replacement behind the stock face plate. This will eliminate the Module and the stock electrical harness.
I would use VDO or another competitor of Autometer.
Anyone want to "lend" me a broken tach/gauge?
I don't think I trust Ford to help. Maybe Toyota?

Kevin at North Hollywood Speedometer has, to my understanding, done Exactly what you are suggesting. Unfortunately, so far, with many hours being spent attempting to correct this issue, Kevin has not been able to make the rebuilt tach function properly.
 

Bill Briley

GT Owner
Aug 9, 2005
212
Valley Forge PA.
Hummmmmm. Thanks for the info.
 

junior

GT Owner
Mar 9, 2007
1,151
So Cal
It took GM a long time to fix the shifter rattle on the C6-ZO6 (I had an '07, fixed after 7 months of complaints), finally they acknowledged the problem and came up with a permanent fix, I am a little discouraged about the fix for the Tach form Ford, over 250 posts and over 8500 views on this forum, and not a word from Ford,...., yet :tap:
 

GT35065

GT Owner
Mark II Lifetime
I just talked to the Ford tech that was helping me on my tach and temp guage issue. It has been over a month now and he is not coming up with anything. Does not want to replace the module as he has no idea if that is the problem. Guess I'll be whistling dixie until someone can come up with a fix. Really annoying that we can't get Ford's attention to at least tell us what to do. I'll try and get a Ford service rep involved and see if they can come up with anything.
 

Kayvan

GT Owner
Jul 13, 2006
4,782
On the half-shafts it affected ~1% of cars; a post with a runnnig tally of VIN #, production/fail dates, mileage and multiple supporting posts were collected, and forwarded to Ford.

That has not happened here, yet; the poll is at just 40 cars, with 2/3rd not using the charger or having battery issues.

Its a %, sampling, failure rate issue.

Until 1% people step up with VIN#, production date, mileage, fail date, stats in hand in a petition, I doubt this will get official response.

http://www.fordgtforum.com/forums/showthread.php?t=4423&highlight=half+shafts
 
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BlackICE

GT Owner
Nov 2, 2005
1,416
SF Bay Area in California
Half shafts are a BIG safety issue, the tach is not.

You can have 100% of the tach fail and not have a recall. Many cars come from the factory without of tach and the FGT car has a rev limiter, so the tach could be view as a non-essential part. Would you expect Ford to fix, recall, or redesign window regulators after the warranty expired if even 10% of the cars had failures?

IHMO it would be nice, but unexpected, for Ford to do anything for non-safety related issues for a car out of production for almost 5 years and out of warranty. These cars don't come unwritten lifetime warranty. I have heard of much bigger problems on Fcars that Ferrari doesn't do anything about and the customers just keep smiling and buying Fcars.

Owners of limited production exotics play in a different world from high volume production cars.
 
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hollywoodstunts

GT Owner
Apr 25, 2009
167
Venice, CA
On the half-shafts it affected ~1% of cars; a post with a runnnig tally of VIN #, production/fail dates, mileage and multiple supporting posts were collected, and forwarded to Ford.

That has not happened here, yet; the poll is at just 40 cars, with 2/3rd not using the charger or having battery issues.

Its a %, sampling, failure rate issue.

Until 1% people step up with VIN#, production date, mileage, fail date, stats in hand in a petition, I doubt this will get official response.

http://www.fordgtforum.com/forums/showthread.php?t=4423&highlight=half+shafts

Don't understand why the 1% number continues to be used. If there are 1000 members on the forum, and 40 failures, that's 4%. I'm willing to bet there are more as apathy takes its toll on everyone being included in our unscientific poll.

Gauges should not fail. Definetly not anywhere approaching 4%. According to an AutoMeter representative, their failure rates are in the 1/10's of a percent. If they are failing at anywhere near 5%, he couldn't imagine Ford not doing something.

Ford is aware of the problem. At least I made Ford aware of the problem. Ford declined offering any sort of assistance with the repair because "I was not the original purchaser of the car" despite the large number of failures I pointed out. Ford also pointed out my car was out of warranty coverage(two months).
 

hollywoodstunts

GT Owner
Apr 25, 2009
167
Venice, CA
Why Ford's continue to be compared to Ferrar'is also is troubling. If I bought a Ferrari, I would expect a tempermental exotic. I didn't. I bought a Ford. Made b the same people that made the Taurus and the Escort. Ford is not known to make tempermental, problematic cars. If I wanted one of those, I would have bought a Ferrari.
Granted it's a limited production car. So is the Porsche Turbo, or Audi R8, but people don't make excuses for those cars.
There's a problem here. And most of the cars affected are not "5 years old" and I don't think the GT's should come with an unlimited warranty, however that would be nice. But if there's a problem that is a result of a manufacturing defect, I think the manufacturer should stand up and fix the problem.
On the other hand,if you're ok with nagging problems, go buy an "F car."