78 K5 dead Tachometer

[K5Germany]

Hi guys,

My name is Ulli and im from Germany. I've been reading a lot here in the forum about a year since I bought a completely rusted Blazer.
Now 12 month Later the Truck is almost done and im driving it almost daylight to work. But suddenly yesterday my Factory Tachometer stopped working. Ignition off, the needle is a bit under 0. Ignition on, the needle jumps to 0. the Truck runs normal and I checked the Tach output from the Distributer, my check lamp flashes. unfortunately I don't know what to do next.

Im sorry that my first post is a question but I need your Help

Here are some photos of the Truck, In Germany these Trucks are very rare so we got to choose, Spend a lot of money for a good Truck or wait and the the cheapest shitbox and build it.

 

[K5Germany]

 

[jake 03]

I would check that you have tach signal at the back of the tachometer. If you do then the tachometer has died. If not you have a wiring problem somewhere.

Good work on the blazer,it looks great!

 

[K5Germany]

Thanks Jake,

I tried to check Tach signal but im not sure how to do it. I hooked a test light between tach signal and ground. Nothing.

 

[rampage]

No help on the tach, but damn! Good job on all that body work.

 

[82355]

You don't have another tachometer, by chance? Just a cheapo aftermarket one?

Damn that thing was rough. Great work fixing it.

Martin

 

[K5Germany]

I found an old Tester, I've got a good Tach signal so the Tachometer is bad Thanks for your help, i try to get it repaired or buy a new one

Ulli

 

[dyeager535]

I want to say there is a chip that goes bad in those that is actually pretty simple to repair. If you can do that body work you can probably accomplish some soldering.

Probably some confirmation necessary that all the tachs are the same (I suspect most/all are the same vintage) but this article talks about fixing a dead tach http://www.howtoalmanac.com/kevin/projects/automotive/tachfix.htm

 

[K5Germany]

Hey Thanks a lot. Its my second Project Truck. i'm slow and definitely never os good like a professional but it's enough for me. i hate nothing more than letting someone else do something for me i could do myself.

Anyway, Thanks for the Link. its a Major help, im going to order the chip and solder it in

Ulli

 

[ZooMad75]

Sucks about the tach, but holy crap dude that's a helluva good job bringing one back from the dead. I thought the rust belt guys had it bad.

Bravo. Well done.

 

[USSkoval]

That's a nice job taking care of all that rust, and the crash damage too!

What's the scoop on those bumpers? They look like factory bumpers, but with a smooth face instead.

 

[K5Germany]

Hey USSkoval,

The Bumper Job was fun. I hate the look of the original Bumper with the plastic inserts plus the rear one was badly bend. So i build the rear one from scratch and modified front one. I welded pieces of sheet metal into the low spots where the plastic belongs to. And then, again, a lot of bonds Time XD

 

[K5Germany]

Ok Little Update on The Tachometer.

I Soldered in a new IC chip into the Circuit Board of the Tachometer but it won't help. Now im going to order a new Circuit board.

But thanks for your Help !

Ulli

 

[dyeager535]

Well darn! Glad they have replacement parts now at least, for awhile there wasn't much in the way of options!

 

[6872xtc]

Ok Little Update on The Tachometer.

I Soldered in a new IC chip into the Circuit Board of the Tachometer but it won't help. Now im going to order a new Circuit board.

But thanks for your Help !

Ulli

If you think about it, would you post up a picture of your repair? I am curious since I have only had one factory tachometer and never had to repair it.

And nice job fixing your truck!