Rev Counter No Working
Rev Counter No Working
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roy e6

Original Poster:

1,025 posts

262 months

Tuesday 1st July 2008
quotequote all
Title supposed to say Rev Counter NOT Working banghead
Having fitted new 5.3 v8 developments engine and omex engine management i have a problem. I cant seem to get the rev counter to work. Omex have supplied a little black box that is supposed to operate it. Having fitted a third one it still does'nt work. Has anybody out there had any problems like this, if so what did you do to get it working? Also if anybody has fitted a 5.3 engine what temperatures are you operating at oil and water. Thanks in advance
Roy.

Edited by roy e6 on Tuesday 1st July 20:14

Uncle Fester

3,114 posts

238 months

Tuesday 1st July 2008
quotequote all
I had this with my Emerald. It needed a tacho driver. I guess that's what the box is. Do you have to turn it on in the software?

roy e6

Original Poster:

1,025 posts

262 months

Tuesday 1st July 2008
quotequote all
Uncle Fester said:
I had this with my Emerald. It needed a tacho driver. I guess that's what the box is. Do you have to turn it on in the software?
Yep thats what the little black box is, but i am on my third and still no luck. will be on the phone to omex tommorow. It starts to work after about 3 minutes then just does what it wants to do.

Edited by roy e6 on Tuesday 1st July 21:29

trackcar

6,453 posts

256 months

Tuesday 1st July 2008
quotequote all
I often have this issue .. i put it down to the ecu not supplying a waveform that the tacho will recognise (isn't teh tacho driver just a step up transformer?) .. I use the tachos out of any post 1997 V8 cerbera as that is driven direct by an MBE in that install so it works great with aftermarket ecus in RV8 cars.

roy e6

Original Poster:

1,025 posts

262 months

Tuesday 1st July 2008
quotequote all
trackcar said:
I often have this issue .. i put it down to the ecu not supplying a waveform that the tacho will recognise (isn't teh tacho driver just a step up transformer?) .. I use the tachos out of any post 1997 V8 cerbera as that is driven direct by an MBE in that install so it works great with aftermarket ecus in RV8 cars.
I thought the tacho driver was supposed to transform the waveform from the ecu, to one that the tacho will recognise. I thought the tachos from a 97 cerb were the same as the ones in a 97 griff?

shpub

8,507 posts

302 months

Wednesday 2nd July 2008
quotequote all
The Griff rev counter gets its input pulses from the coil and sees several hundred volts from the coil back emf so 12v from the ECU doesn't do anything. The Cerbera rev counter is designed to work with a 12 V pulse. Connect it up and it just woks.

The black box is normally a relay or small coil that replicates the ignition coil and generates the EMF to trigger the rev counter.



roy e6

Original Poster:

1,025 posts

262 months

Wednesday 2nd July 2008
quotequote all
Cheers gents thumbup tacho on way from Bell Hill

Ballistic Banana

14,706 posts

297 months

Wednesday 2nd July 2008
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Paul Dove made my Loom with a tacho Driver in and it works superbly smile including the Shift light that was also in the loom and using some nice bright LED in the unused window in the bottom of my Tacho cool

Maybe Paul uses a different tacho driver that the other guys that would work on yours....would save changing the tacho?

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