Club G40 Forum

Technical => Electrical => Topic started by: mk2_Eaton on July 20, 2015, 11:44:56 pm

Title: mk2f engine in mk2 (rev counter issues)
Post by: mk2_Eaton on July 20, 2015, 11:44:56 pm
Anyone know how to get the mk2 rev counter to work with the mk2f style coil pack? From what I can gather the mk2 uses a negative rev counter signal from the coil, where the mk2f uses a positive signal from the coil. How have people got the mk2 rev counter to work when doing GT/G40 conversions?
Title: Re: mk2f engine in mk2 (rev counter issues)
Post by: kwijibo_coupe on July 21, 2015, 12:46:57 am
On the coil next to the plug you'll notice a flap you can lift up. Under this you'll see two terminals. Hook a wire into the terminal marked '1' then feed this wire through to behind the clocks and connect it to the red wire with the black tracer going into the clocks.
Title: Re: mk2f engine in mk2 (rev counter issues)
Post by: Andy on July 21, 2015, 11:20:22 am
Rev counter is ECU-driven on a 2f (and most Digifant systems), so if you've got the 2f engine bay harness you can pick the wire up from there.

It's pin 24 of a GT or G40 ECU, a 0.5mm² green wire - which then splices to a red/black stripe 0.5mm² wire to go into the cabin. The interface is through the bulkhead connector behind the fusebox if memory serves, so might save you running a directly from the coil.
Title: Re: mk2f engine in mk2 (rev counter issues)
Post by: mk2_Eaton on July 24, 2015, 12:57:17 am
It's actually a afh engine conversion Andy but my thinking was more people will of done the gt into mk2 and they used the same coil pack. I've tried splicing the rev counter feed from the ecu into the clocks with no joy. I checked the signal wire from the coil (people have wired this straight into the mk2f rev counter before) and it's a positive signal. From memory doesn't the mk2 takes its signal from the negative side of the coil?

It could just be that the rev counter is shafted but I haven't got another car to test it on
Title: Re: mk2f engine in mk2 (rev counter issues)
Post by: mk2_Eaton on July 24, 2015, 10:06:15 pm
All sorted now kwijibo_coupe's suggestion did the trick. Cheers to both of you for the help