New charger specialties tic toc tach issues.....fixed! :o)

[70charginglizard]

I recently bought a new tic toc tach from charger specialties and put it in the liz. I installed it using a new tic toc tach harness I also bought from them and hooked everything up per the harness and tach instructions but for some reason the tach is jumping around when running.
The clock is doing something weird as well. It stops working as soon as I turn the headlights on which is really weird to me seeing that the 12v power source I used doesnt even come close to the headlight switch. I ran a straight wire to the battery and put an in line fuse between the battery and it.
Any idea what might be causing my issues here?

Here is how I hooked it up.

Ran the white off the clock straight to the battery and put an in line fuse between it.

Ran the grey wire from the terminal on the tic tock tach to the negative terminal on the coil.

Ran the blue wire from the round stud on the tic tock tach to one of the blank non used accessory fuse box terminal.

[skip68]

Do you have an MSD ignition box ?

[70charginglizard]

Do you have an MSD ignition box ?

Nope. Everything is pretty standard under the hood regarding the ignition system.

[skip68]

        I need to think some more.   Nice clean engine compartment.   

[troutstreamnm]

Are the other instruments working properly and is your instrumental panel in the dash frame?  I just fixed a wiper motor electrical problem and noticed that all my gauges were doing wierd things if the instrument panel was not in the dash frame.  When the panel went fully into the frame everything worked normally.  Probably a ground issue.  Just curious if your panel was in or out of the dash frame?  

[skip68]

I was just thinking a ground too.   

[70charginglizard]

Are the other instruments working properly and is your instrumental panel in the dash frame?  I just fixed a wiper motor electrical problem and noticed that all my gauges were doing wierd things if the instrument panel was not in the dash frame.  When the panel went fully into the frame everything worked normally.  Probably a ground issue.  Just curious if your panel was in or out of the dash frame?  

I kinda thought about that one as well. All other gages are working just fine and the instrument panel is solidly place in the car. I did not remove it to put this new tic toc tach in.

I just pulled the old clock out thru the back and then put the new tick toc tach in from the back and then screwed it all in and connected up all the wiring.

These tic toc tacs are kinda weird that way. No ground wire what so ever. It must get it's ground using the interfacing contact of the tach to the instrument cluster I assume.

I was only able to get two of the three tic toc tack mounting screws in. Perhaps thats my problem.  

[71_deputy]

sounds like a grounding problem as stated- I always use a grounding wire from the dash frame to the cluster metal frame!!!

[70charginglizard]

sounds like a grounding problem as stated- I always use a grounding wire from the dash frame to the cluster metal frame!!!

I'll try that tonight when I get home.

Thanks for the tip. I'll let you know if it works.

[70charginglizard]

sounds like a grounding problem as stated- I always use a grounding wire from the dash frame to the cluster metal frame!!!

I'll try that tonight when I get home.

Thanks for the tip. I'll let you know if it works.

Yep that was it. That one little screw I left out was where the backlight plugs in and that must be where the tic toc tach gets its ground from.


Problem solved. Works great now. Thanks for the tip guys. Much appreciated. 

[troutstreamnm]

  Good job.  I can't believe I helped someone with an electrical problem 

[resq302]

Good job.  I can't believe I helped someone with an electrical problem 

There's a first time for everything.

[71_deputy]

10-4!

[bull]

Are those tachs still off from the originals? Seems they were clocked like 500 rpms different than the OE ones and the number font was off too.