MR2 Roadster Owners Club

The Workshop => Audio / Security / Electrical => Topic started by: roger on October 12, 2009, 13:55

Title: Digital tacho & shift light
Post by: roger on October 12, 2009, 13:55
Before I start taking things apart, can anybody point me in the right direction as my knowledge is nil.

Apart from switched live and ground, the only other wire is to the tacho. Instructions aren't much help, just say put it to the coil or ECM.

Looking at wiring diagrams there is a white wire out of ECM for tacho. I'm assuming it goes all the way to the unit.

There is also a "Splice Point" (I1) in passenger footwell for this part of the loom.

So the question is should I go back to the ECM (or E-manage loom), use the splice point (I assume this is what it is for), or can I just piggy-back it to the connector on the tacho unit or splice into the wire there?

Or, am I completely loosing the plot and should be doing something else?

Thanks guys.
Title: Re: Digital tacho & shift light
Post by: muffdan on October 12, 2009, 14:33
On the splicing front, you can splice it in anywhere you like! Personally I'd splice in wherever is convenient and takes the least amount of time, probably just behind the tacho   s:oops: :oops: s:oops:
Title: Re: Digital tacho & shift light
Post by: roger on October 12, 2009, 15:53
Thanks Jason. Probably not doing until weekend, so unless anybody has any other tips or pointers I'll consider it closed. Ta.
Title: Re: Digital tacho & shift light
Post by: markiii on October 12, 2009, 16:00
Rog do you have a Profec I forget?
Title: Re: Digital tacho & shift light
Post by: roger on October 12, 2009, 16:05
Quote from: "markiii"Rog do you have a Profec I forget?

No. I assume it could be wired to that??
Title: Re: Digital tacho & shift light
Post by: markiii on October 12, 2009, 16:50
yep Profec has an RPM feed which you would have wired to the boomslang harness anyway

in which case teh best place to tap into is the boomslang harness to leave your stock wiring untouched

that said its going to need a long wire

I might be tempted to splice behind teh cluster for convenience, but ideally go back to teh boomslang

I suggest use some cat 5 network cable then you have capacity to use teh other cores for something else, if you go that route give me a shout and I'll stick some in teh post I have about 100m reel in teh garage
Title: Re: Digital tacho & shift light
Post by: roger on October 12, 2009, 16:59
Mmmmm - I'll have a think. Not too difficult to feed through. Got to splice onto the 6" wire from the gauge anyway (unless I can undo it). As you say it does leave the OEM alone, just in case. Whilst searching before my first post I saw you had a tacho problem when you first Hass'd, which was down to grounding, so I'm assuming this wouldn't be affected by that??

Thanks for the tip about Cat5. We've got a huge amount here, so whilst your offer is appreciated I can source OK.   s:wink: :wink: s:wink:
Title: Re: Digital tacho & shift light
Post by: markiii on October 12, 2009, 17:04
it was down to my dodgy wiring

When I first went Turbo teh boomslang wasn;t available and I had to build my own

  s:oops: :oops: s:oops: