Rev counter

[brainbug007]

After getting all the redundant wiring out of the loom and everything working except the lights and megajolt, it's just the rev counter I need to get working now. I've put the green wire from my edis into the right pin on instrument cluster (see attached picture) but when I run the engine the rev counter doesn't move :( I checked the voltage at the pin and with the key in position 2 and the engine off, it reads around 0.05v, with the engine running & idling, I get a reading around 0.35-0.39 (fluctuates). So would this mean the sierra instrument cluster handy andy gave me isn't compatible with an edis?

[brainbug007]

Thanks adrian, it did help a bit. I must say making the circut with diodes etc is a bit daunting as I've never made anything electrical before! If I have to go down that route, can I get stuff like that from maplins or ebay? I have no idea what to look for as the codes quoted don't mean anything to me :confused: I did come across this http://www.minifinity.com/forum/viewtopic.php?f=5&p=852579 which seems to indicate that pin 11 on the edis might work instead of pin 2 which I've already tried.

[mark]

Thanks adrian, it did help a bit. I must say making the circut with diodes etc is a bit daunting as I've never made anything electrical before! If I have to go down that route, can I get stuff like that from maplins or ebay? I have no idea what to look for as the codes quoted don't mean anything to me :confused: I did come across this http://www.minifinity.com/forum/viewtopic.php?f=5&p=852579 which seems to indicate that pin 11 on the edis might work instead of pin 2 which I've already tried.

You will probably only get it to half read with the edis outputs, you can buy the diode thing already made from trigger wheels and run it from the coilpack which will definately work

[brainbug007]

Ah right so that's what those things are for on trigger wheels. So how do they connect to the coilpack?

[robo]

You can also make it work from the alternator like the diesels do.

Bob

[mark]

Ah right so that's what those things are for on trigger wheels. So how do they connect to the coilpack?

They have 2 wires going in and one coming out, the single wire goes to rev counter and the other two go to opposite sides of the coil pack

[brainbug007]

So do the wires just go onto the plug that connects the edis to the coilpack?

[mark]

So do the wires just go onto the plug that connects the edis to the coilpack?

Basically, yes!

You have a pm by the way

[steve8274]

i have megajolt on my car and am using megajolt.
on my megajolt, one of the wires says tacho out. think its a blue wire.
i connected this to my rev counter and it works on tickover, but when i rev it, it goes to zero.
i rang etb up and they said i need to connector a 1k ohm resistor or maybe diode (cant remember now) between battery and the blue wire.
i have bought the part from maplins but havent fitted yet, mainly because i dont know how to. its just a piece of thin wire with a thing in middle. not sure how to connect this to battery and wire.
dont know if you have this wire but maybe able to wire your rev counter this way if you know what you doing.
if not, someone else may tell us how to do it;)
hth
steve

[robo]

This was in passion ford http://img.photobucket.com/albums/v490/sibster/TachoWiring.jpg and this http://trigger-wheels.com/store/contents/en-uk/d58.html

Bob

[brainbug007]

Thanks Bob, that passion ford picture confirms what I thought :) I'm gonna have a go at making the loom bit with diodes as they only cost £2 off fleabay for enough to make 10 looms so if anyone else wants one let me know ;)

[baz-r]

looking at that simple little circuit using two diodes and a zenner its converting the two signels from each coil (4 cyl wasted spark is two coils) to a single coil and dizzy type signel to run a std tacho

[mark]

looking at that simple little circuit using two diodes and a zenner its converting the two signels from each coil (4 cyl wasted spark is two coils) to a single coil and dizzy type signel to run a std tacho

Thats the general idea!

[brainbug007]

Finally got round to creating the bit of loom for this using the diodes, bit of a mission to get it working but I got there in the end with some help from my brother who's good at soldering :) Engine idles around 500 rpm and when reved up, where I thought it was close to the redline from the sound, it's only doing 3krmp :)

[robo]

You could always check calibration of the rev counter with a decent timing light. Some of those rev counters have a trim screw in them.

Bob