Help, Tac output testing

SSDD · Post by **SSDD** » Wed Jun 15, 2005 5:52 pm

Hi all, I think ive broke the taco output components on the PCB. I connected the taco output to the taco wire that used to go to the coil, the taco worked for a few seconds then stopped, Then I disconnected it and tried again and it done the same. Today I built & tried the 2 solutions in the file selection but still nothing, then I tried again connecting the taco output to the wire that runs to the taco (ex coil wire) this time it done nothing, can some one tell me how I can check to see if there is voltage\pulse coming from the taco output, if ive killed it what components do I have to change on the board to get it up and running again ??

Thanks
Steve

Josh_b · Post by **Josh_b** » Wed Jun 15, 2005 6:06 pm

if you have a multimeter see if the tach out from the MJLJ is giving out about 5v, if not then its the MJLJ not working, your should also see if any voltage is coming out of the wire you connected the mjlj to that was previously connected to your coil

SSDD · Post by **SSDD** » Wed Jun 15, 2005 6:34 pm

Ive checked, there is no voltage comiing out of the wire that was conected to the coil (i made sure of that)the Mjlj is working really well but just cant get the taco working, if there is not 5v comming out the tac output what do i have to replace on the board ??

Thanks
Steve

Josh_b · Post by **Josh_b** » Wed Jun 15, 2005 8:59 pm

if you dont get a 5v signal from your MJLJ tach output then suspect Q4, 2N3906, what sort of tach was it you were trying?

SSDD · Post by **SSDD** » Wed Jun 15, 2005 9:27 pm

Dont know the make, its the standard Tach in a 1989 Peugoet 205 rally, the speedo is a Jagger or Jaggar or somthing like that but there is no name on the tach

Thanks
Steve

Post by **brentp** » Thu Jun 16, 2005 6:08 am

"worked for a few seconds and stopped"- sounds like a component overloaded and failed. Yes, the 2N3906 transistor would be suspect.

SSDD · Post by **SSDD** » Sat Jun 18, 2005 12:12 am

Hi All, i check today and ive got about 4.6v comming from the tach output from the megajolt (is that ok or should it be 5V) so ive not damaged anything in there (i hope) ive made all 3 in the files section bu I still can get the f****** tach working, i put the dizy and coil back on the car, fired it up and the tach works, i then disconected the wire that go's to the tach from the coil & the tack stopped working, so ive got the correct wire. Someone help me PLEASE its driving me mad

Thanks
Steve
(now with a lot more grey hair)

Autosport Labs

Help, Tac output testing

Help, Tac output testing

try

Ive checked, there is no volt

if no 5v

Dont know the make, its the s

"worked for a few seconds and

Hi All, i check today and ive