Dash gauges quit working

I installed the new parts and nada.  Nothing.

Wow. I don’t get it. So, just to recap: your speedometer and tachometer operate correctly, but you have no working gauges? Fuel, Temp, Oil Pressure and Amps have no readings? But all your warning lights on the dash work (Brake, ABS, CEL, high beam, turn signals, etc?).

This is a complete guess, but I wonder if there is something wrong with the EEC-IV computer...? Again, a guess. I’m not sure what it might have to do with all of this.

i would ask if you tested the terminals at any of the gauges for voltage, but the likelihood of ALL of them being damaged/inoperative seems remote, unless there was a surge through the IVR that somehow damaged them.

You’re probably pretty fed up with all this by now...but if it were me I would remove the gauges from the instrument panel and test each one for operation. Then, I would test each of the connectors in the IP circuit, where each gauge attaches.

There’s an easier way to do that. First, trace each gauge to its corresponding contact on the male ribbon cable (While it’s attached/connected) and note that. Now, check the continuity from the IP female ribbon circuit connector on the IP to the gauge. Finally turn on the ignition (or start the car) and measure the voltage from each gauge’s connector on the male ribbon connector. This is the same as trying to hold up the IP whilst the ribbon connector is attached to take these current measurements, which doesn’t sound like much fun. Especially considering how delicate that connector is.

What you want here are zeroes across the board, no voltage, or else there is another issue.

Please let us know what you find.

Been awhile since I've had a chance to revisit the bird.  Had a Sport Trac to finish up and then a friends car decided to overheat so I worked on that.

Tonight worked on it a little and another issue.  I have no dash lights which I didn't notice before because I was always working on it during the day and this afternoon it was dusk when I finished and after I started it nothing.  So hows that?

I installed the new parts and nada.  Nothing.

Wow. I don’t get it. So, just to recap: your speedometer and tachometer operate correctly, but you have no working gauges? Fuel, Temp, Oil Pressure and Amps have no readings? But all your warning lights on the dash work (Brake, ABS, CEL, high beam, turn signals, etc?).

This is a complete guess, but I wonder if there is something wrong with the EEC-IV computer...? Again, a guess. I’m not sure what it might have to do with all of this.

i would ask if you tested the terminals at any of the gauges for voltage, but the likelihood of ALL of them being damaged/inoperative seems remote, unless there was a surge through the IVR that somehow damaged them.

You’re probably pretty fed up with all this by now...but if it were me I would remove the gauges from the instrument panel and test each one for operation. Then, I would test each of the connectors in the IP circuit, where each gauge attaches.

There’s an easier way to do that. First, trace each gauge to its corresponding contact on the male ribbon cable (While it’s attached/connected) and note that. Now, check the continuity from the IP female ribbon circuit connector on the IP to the gauge. Finally turn on the ignition (or start the car) and measure the voltage from each gauge’s connector on the male ribbon connector. This is the same as trying to hold up the IP whilst the ribbon connector is attached to take these current measurements, which doesn’t sound like much fun. Especially considering how delicate that connector is.

What you want here are zeroes across the board, no voltage, or else there is another issue.

Please let us know what you find.

Been awhile since I've had a chance to revisit the bird.  Had a Sport Trac to finish up and then a friends car decided to overheat so I worked on that.

Tonight worked on it a little and another issue.  I have no dash lights which I didn't notice before because I was always working on it during the day and this afternoon it was dusk when I finished and after I started it nothing.  So hows that?

It sounds like there’s something going on with your wiring harness to the IP—maybe you’ve got some blown/shorted fusible links. Gauges don’t work, (now) neither do the IP lights.

Or, perhaps an enterprising rodent has decided to occupy that area for a time, and left its mark with chewed/damaged wiring.

I’m not going to lie to you, this is scraping the bottom of the Diagnosis barrel. But it does sound like a wiring harness issue. Follow the bundle of wiring that runs through the firewall into the engine compartment. There have been stories of how wiring got caught up in the steering column yoke and it tore/damaged it. Trace wiring from the IP cluster, follow its path. Somewhere there has to be an answer.

Wiring issues are no fun. I much prefer mechanical fixes, where you can clearly see a part is moving—or not.

Agreed you have a harness issue. Do you have an EVTM for your car? If not, try to find one on Ebay. Without the wiring diagrams you stand zero chance of tracing down the problem.

EEC has nothing to do with operation of the oil, fuel and temp gauges or the tach / speedometer.

I assume you have checked ALL the fuses?

Agreed you have a harness issue. Do you have an EVTM for your car? If not, try to find one on Ebay. Without the wiring diagrams you stand zero chance of tracing down the problem.

EEC has nothing to do with operation of the oil, fuel and temp gauges or the tach / speedometer.

I assume you have checked ALL the fuses?

Just got one off ebay for $35.

I take it these EVTM's are specific for each year for the make/model?  Reason I'm asking is that I put a 1998 5.0 from an Explorer AWD into my 02 Sport Trac.  I've got a wiring issue someplace and need to trace that problem down as well.

I installed the new parts and nada.  Nothing.

Wow. I don’t get it. So, just to recap: your speedometer and tachometer operate correctly, but you have no working gauges? Fuel, Temp, Oil Pressure and Amps have no readings? But all your warning lights on the dash work (Brake, ABS, CEL, high beam, turn signals, etc?).

This is a complete guess, but I wonder if there is something wrong with the EEC-IV computer...? Again, a guess. I’m not sure what it might have to do with all of this.

i would ask if you tested the terminals at any of the gauges for voltage, but the likelihood of ALL of them being damaged/inoperative seems remote, unless there was a surge through the IVR that somehow damaged them.

You’re probably pretty fed up with all this by now...but if it were me I would remove the gauges from the instrument panel and test each one for operation. Then, I would test each of the connectors in the IP circuit, where each gauge attaches.

There’s an easier way to do that. First, trace each gauge to its corresponding contact on the male ribbon cable (While it’s attached/connected) and note that. Now, check the continuity from the IP female ribbon circuit connector on the IP to the gauge. Finally turn on the ignition (or start the car) and measure the voltage from each gauge’s connector on the male ribbon connector. This is the same as trying to hold up the IP whilst the ribbon connector is attached to take these current measurements, which doesn’t sound like much fun. Especially considering how delicate that connector is.

What you want here are zeroes across the board, no voltage, or else there is another issue.

Please let us know what you find.

Been awhile since I've had a chance to revisit the bird.  Had a Sport Trac to finish up and then a friends car decided to overheat so I worked on that.

Tonight worked on it a little and another issue.  I have no dash lights which I didn't notice before because I was always working on it during the day and this afternoon it was dusk when I finished and after I started it nothing.  So hows that?

It sounds like there’s something going on with your wiring harness to the IP—maybe you’ve got some blown/shorted fusible links. Gauges don’t work, (now) neither do the IP lights.

Or, perhaps an enterprising rodent has decided to occupy that area for a time, and left its mark with chewed/damaged wiring.

I’m not going to lie to you, this is scraping the bottom of the Diagnosis barrel. But it does sound like a wiring harness issue. Follow the bundle of wiring that runs through the firewall into the engine compartment. There have been stories of how wiring got caught up in the steering column yoke and it tore/damaged it. Trace wiring from the IP cluster, follow its path. Somewhere there has to be an answer.

Wiring issues are no fun. I much prefer mechanical fixes, where you can clearly see a part is moving—or not.

I'm with you.  I hate wiring issues and much prefer mechanical as well.  Plus I just ordered the EVTM that Jeff K mentioned.  I will need to find where the grey/yellow wire is coming from since that is the main wire coming into the IP cluster and I hate that I can't go to napa, oreilly or autozone and get the proper wire colors and have to special order them.  

But bonus.  I found a 88 in a junkyard only 150 miles away from me so I have some parts I can get if need be.  Got my replacement T-5 from him for $300 this past weekend.

That grey/yellow wire that runs by itself from the ignition switch to the cluster is a "special" resistance wire that runs from key on power to the stock mechanical/thermal IVR. Resistance is around 8 ohms if I remember correctly, and is "all by itself" because it does generate some heat that needs to be dissipated which it would not be able to dissipate if it was bundled up in a harness with other wires.

Troubleshooting electronics is fun!! I have been reading circuit diagrams and building electronics projects since I was 12 years old, and have gotten pretty good at it in the last 52 years. I spent my carrier as a physicist and electrical engineer. When I worked in the power generation and distribution industry I designed and built a crap load of one off testing and validation pieces of equipment for my employer, and when I got into education, I taught physics and electrical engineering at one of the highest rated engineering colleges in the country.

That grey/yellow wire that runs by itself from the ignition switch to the cluster is a "special" resistance wire that runs from key on power to the stock mechanical/thermal IVR. Resistance is around 8 ohms if I remember correctly, and is "all by itself" because it does generate some heat that needs to be dissipated which it would not be able to dissipate if it was bundled up in a harness with other wires.

Troubleshooting electronics is fun!!  I have been reading circuit diagrams and building electronics projects since I was 12 years old, and have gotten pretty good at it in the last 52 years.  I spent my carrier as a physicist and electrical engineer. When I worked in the power generation and distribution industry I designed and built a crap load of one off testing and validation pieces of equipment for my employer, and when I got into education, I taught physics and electrical engineering at one of the highest rated engineering colleges in the country.

Yeah I guess it depends on your perspective. When I was younger I hated electrical troubleshooting as I did not have the patience for it. As I have grown older that’s changed.

It also helps that I made a point to educate myself on the various concepts and components.

In 1974 when I was 17 I “grafted” a power transformer from an old record player into a 1920s Philco phonograph/AM/short wave radio. It wasn’t all that hard—there were schematics for both inside each device, so it was just determining if the outputs matched and where the wires went. Afterwards it worked for years, until the tubes started to burn out and it was not worth it (at that time) to replace them. Looking back I am still kind of amazed that I did that, and didn’t burn down the house.

That grey/yellow wire that runs by itself from the ignition switch to the cluster is a "special" resistance wire that runs from key on power to the stock mechanical/thermal IVR. Resistance is around 8 ohms if I remember correctly, and is "all by itself" because it does generate some heat that needs to be dissipated which it would not be able to dissipate if it was bundled up in a harness with other wires.

Troubleshooting electronics is fun!!  I have been reading circuit diagrams and building electronics projects since I was 12 years old, and have gotten pretty good at it in the last 52 years.  I spent my carrier as a physicist and electrical engineer. When I worked in the power generation and distribution industry I designed and built a crap load of one off testing and validation pieces of equipment for my employer, and when I got into education, I taught physics and electrical engineering at one of the highest rated engineering colleges in the country.

Yeah I guess it depends on your perspective. When I was younger I hated electrical troubleshooting as I did not have the patience for it. As I have grown older that’s changed.

It also helps that I made a point to educate myself on the various concepts and components.

In 1974 when I was 17 I “grafted” a power transformer from an old record player into a 1920s Philco phonograph/AM/short wave radio. It wasn’t all that hard—there were schematics for both inside each device, so it was just determining if the outputs matched and where the wires went. Afterwards it worked for years, until the tubes started to burn out and it was not worth it (at that time) to replace them. Looking back I am still kind of amazed that I did that, and didn’t burn down the house.

Well I figured out what caused the issue.  Mice.  Effing mice.  Time to get vehicles prepped for winter and finishing up and I open the hood and there is a mouse in the hood header.  Hooked up my shop vac to try and suck that little pest but man they can jump.  He spun around and went under the car.  Charged up the battery, started the car and when the ac turned on out he runs.  Just checked and one dead mouse in the trap.  Let's see what tomorrow brings.

So I'm thinking of next year ripping the entire car apart and replacing the wiring harness since the previous owner really hacked into the wiring and replacing the wiring harness is really and truly the only cure.

I'm going to check with some youtubers to see if they might be interested in ripping the car down and replacing the wiring harness.

That grey/yellow wire that runs by itself from the ignition switch to the cluster is a "special" resistance wire that runs from key on power to the stock mechanical/thermal IVR. Resistance is around 8 ohms if I remember correctly, and is "all by itself" because it does generate some heat that needs to be dissipated which it would not be able to dissipate if it was bundled up in a harness with other wires.

Troubleshooting electronics is fun!!  I have been reading circuit diagrams and building electronics projects since I was 12 years old, and have gotten pretty good at it in the last 52 years.  I spent my carrier as a physicist and electrical engineer. When I worked in the power generation and distribution industry I designed and built a crap load of one off testing and validation pieces of equipment for my employer, and when I got into education, I taught physics and electrical engineering at one of the highest rated engineering colleges in the country.

Yeah I guess it depends on your perspective. When I was younger I hated electrical troubleshooting as I did not have the patience for it. As I have grown older that’s changed.

It also helps that I made a point to educate myself on the various concepts and components.

In 1974 when I was 17 I “grafted” a power transformer from an old record player into a 1920s Philco phonograph/AM/short wave radio. It wasn’t all that hard—there were schematics for both inside each device, so it was just determining if the outputs matched and where the wires went. Afterwards it worked for years, until the tubes started to burn out and it was not worth it (at that time) to replace them. Looking back I am still kind of amazed that I did that, and didn’t burn down the house.

Well I figured out what caused the issue.  Mice.  Effing mice.  Time to get vehicles prepped for winter and finishing up and I open the hood and there is a mouse in the hood header.  Hooked up my shop vac to try and suck that little pest but man they can jump.  He spun around and went under the car.  Charged up the battery, started the car and when the ac turned on out he runs.  Just checked and one dead mouse in the trap.  Let's see what tomorrow brings.

So I'm thinking of next year ripping the entire car apart and replacing the wiring harness since the previous owner really hacked into the wiring and replacing the wiring harness is really and truly the only cure.

I'm going to check with some youtubers to see if they might be interested in ripping the car down and replacing the wiring harness.

NOW you are getting somewhere!

While I’m certain that’s not the result you wanted to find, at least now you know what the problem is, so that’s a positive step. And yes, I completely agree that even though it will be a MAJOR undertaking, replacing the harness is clearly the best way to go here.

Best of luck when that time comes, and stay in touch. Might I suggest you use the time this winter to locate a used—in good condition—wiring harness?

Those darn critters can do a lot of damage! A few years ago I had my TC parked out on the slab next to my garage / shop for a month or so during the winter. Went out to start it up, which I would typically do every few weeks just to let it run until the fluids came up to temp (I dont drive my Tbirds when there is salt on the roads). ABS light on. Wasnt on a few weeks before and the car had been last run. A check of ABS codes showed driver rear ABS sensor open circuit. Crawl under car, and find cable from ABS sensor chewed in half. Took out sensor and cable and spliced it back together, and put it back in. No ABS light. Fast forward 3 or 4 weeks..... Go out to start it and let it run again. ABS light on with same code for driver rear sensor open circuit. Crawled under car. CABLE CHEWED IN HALF AGAIN RIGHT AT MY REPAIR!!! Took cable and sensor out re spliced cable together and put the TC back in the garage / shop. Problem solved.

2 summers ago I hopped into the 05 Taurus SEL Premium Duratec to go to an appointment. CEL pops on within 30 seconds of starting the car. Wasnt on last time I drove it a few days prior. Took another car to the appointment. Upon returning, ran codes. 4 different O2 sensor codes for the B2S1 sensor. Pop open hood. All 4 wires to sensor chewed off right at the O2 sensor so I couldnt even splice the wires. $35 for a new O2 sensor from RA and no CEL.