Speedo not working on TRD center tach coversion

[SickCelica696]

Hey my speedometer has been kirking out for awhile on my center tach conversion. It'll work fine and then randomly just shoot up and down, sometimes to the pedal pressure. My question is for sean or anyone else thats had similar problems. I'm pretty sure the wiring on the back of the board is find I just want to know what the metal squares on the front of the board affect. I believe mine are not cut properly and might be causing this problem.

[02celica]

I would say talk to dooly about it. maybe?

[LEDmod]

90% of the time is that coppoer foil wasn't cut enough.....
One simple way to check is using continuity from multimeter... continuity is way to check if the electricity flows or not....

If you can show me close up picture of where you cut the copper foil, I can diagnose the problem instantly...

Also other 10% of the problem would be leg of the needle motor base is touching the needle motor, causing short circuit(nothing permanent)....

[SickCelica696]

I know its not the foil. I recently tried cleaning up the legs better on the front and I think I made it worse. can you pm or email me a pic of the install?

[LEDmod]

Best thing is to take close up picture of the front and back area..
I can find the problem pretty much right away..

But here is a step by step guide...
http://newcelica.org/forums/showthread.php?t=205567

[SickCelica696]

Instead of bending them out 90 degree's I think I just cut them off, would that matter?

[vyets]

hey thats what happened to mine last time
my RPM just stopped working unless i reved it real hard then it owuld jump, i just took it apart and put it back together and it works fine ever since.

[DYI01]

I had a problem where the insulation on the one of the wires was damaged so I wrapped it in electrical tape and its been fine since.

[SickCelica696]

Now sometimes it'll shoot up and act like a vacuum/boost gauge. Depending on the throttle postion I can go 0-140 in about 4 seconds lol.



This is actually a fun game driving around like this. It's like russian roulette on if im getting a speeding ticket or not. Atleast now I can really say "No officer I really don't know how fast I was going"

[SickCelica696]

I forgot about I changed the clutch last week. I bet the harness for the VSS is loose. I'll double check that.

[S|Lv3rBu||et]

Hopefully it's not your tranny speed sensor going south... :ugh:

[LEDmod]

Instead of bending them out 90 degree's I think I just cut them off, would that matter?

Cutting it off would be best way....
So leg isn't the one causing the problem...
Just take a close up picture of the circuit....

[Seven-Of-Nine]

SickCelica696 your best bet is to take the board out again, and double check the wiring also re-slice the copper on the PCB, make it nice and deep, completly clip off the leg on the motor pots use new sharp cutters not old end snips. and finally using long nose pliers pinch the centre of the motor leg blades on that pot closer so a better contact is made. Could be worth checking that you havn't pushed the needles down too much so they are sticking.

[SickCelica696]

No I've checked alllll that stuff multiple times. I'm 90% sure right now its the VSS being loose and not sending the signal. Once I confirm I'm getting a good speed reading I'll rip apart the thing again and take pics..