Just arrived at the destination in Florida and on startup I see that the tach and temps/fuel gauges are not working. Any ideas for a first look see ? Loose wire or fuse serving both ? Older IM Roadster. Thanks.
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I bet'cha they both have the same fuse feeding ignition switched 12 volts to them.
BUT! Given the road vibration from the trip, I would get under the dash to look for a loose 12 V to them. I've attached the circuit diagram of the back of typical VDO gauges.
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David, what Gordon said.
IF your car is wired like his diagram, it looks like power is daisy chained from the combi gauge to the tach, so wherever that comes from may have shaken loose. The diagram says it comes from the wiper switch, but each builder has his own way of wiring so yours may get power from another 12V source.
I'd check under my dash, but VS almost certainly did it differently than IM or the original P wiring.
On the chance that your wiring is like the diagram, you might try turning on the wipers to see if they're also out.
It might also be a ground that has shaken loose. Do the instrument lights come on when you turn on the headlight switch? If so, the ground is probably OK.
Tks, Mitch. Wipers and lights work fine. I!ll get under there today.
If the dash lights(gauge backlighting) work then I'd look at 12 v power to the combi gauge and tach.
There is no gauge power needed for the speedo.
If the backlights don't work I'd suspect a ground is loose from all three gauges. The ground is usually daisy-chained, as is the backlight.
Shouldn't be too bad to fix other than getting yourself under there....
I find it's easiest to get under the driver's side by laying in there from the passenger side, and use some pillows.
Update....15amp fuse was blown from the fuse box which powered the tach then combo gauge. Brought a separate +12v fused from ignition switch to the combo gauge and it works fine. Put a new fuse in the original power to the tach and it did not blow but the tach now won't work. I'm thinking the tach may have gone US. The tach is not important right now so i'll look into it more when back home. Thanks for the tips.
Glad you got it sorted out, Dave.
With the cold today, I wish I was down there with you.
By the way, how's the windshield holding up? 
David:
Where are you in Florida? If you are anywhere near the Panhandle and need anything, let me know. I've got lots of tools etc. if you run into any more trouble.
Bob: IM S6 posted:Glad you got it sorted out, Dave.
With the cold today, I wish I was down there with you.
By the way, how's the windshield holding up?
Thanks
About 60F. And gale warnings
Pyss off as usual.....
Yeah, we aren't exactly having a heatwave down here. Pretty good winds as well, but not gale force where we are.
We are going to be right on the Gulf tonight for a party. Coats and rocks in our pockets may be in order.
Panhandle Bob posted:David:
Where are you in Florida? If you are anywhere near the Panhandle and need anything, let me know. I've got lots of tools etc. if you run into any more trouble.
Very nice of you Bob, thanks. We're over in Flagler Beach, waterfront looking at an angry Atlantic right now. Weather is still way better than home though. We'll be up and down this coast for another two weeks then thread the needle ( avoid snow storms ) in Pa, Ny to get home. If anything serious goes wrong I'll throw the little bugger on the trailer and spend more time at happy hours.
Sorry you aren't closer! The Gulf here kicks up this time of year, but not like the Atlantic.
Today it's about 55 and yesterday it was about 72. 35 mph winds.
Stay warm. Flagler beach has an interesting history. A friend of our sons is in college there. School only has a few hundred students and the campus is an old resort I think.
Panhandle Bob posted:Sorry you aren't closer! The Gulf here kicks up this time of year, but not like the Atlantic.
Today it's about 55 and yesterday it was about 72. 35 mph winds.
Stay warm. Flagler beach has an interesting history. A friend of our sons is in college there. School only has a few hundred students and the campus is an old resort I think.
We've enjoyed Flagler's history for some time. Last night we caught a documentary called Titans wherein Flagler assisted Rockefeller build up Standard Oil. We stayed on Jekyll Island a few nights last weekend.
David , We sorta passed by each other schedule wise. We left The Villages, FL. 2/20 for home.
My tach failed on my first Spyder because the internal ground had failed and the case itself was not grounded...... Try grounding the tach case to a "known" good ground....
Cheap fix if it works..... 
Being an IM I am almost positive your tach is a good VDO one. When I ordered my VS almost 16 years ago it came with a non working Chinese repro tach. Kirk kindly sent a replacement one that worked for a short while and then it died. I got tired and sent it to North Hollywood Speedometer where they swapped the innards for a VDO mechanism; 15 years later it's till working as it should. Those Chinese repro gauges have a certain reputation.....;-P