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I have recently acquired an original petrol tacho to replace the clock in my T25 which I have fitted but I have two problems.
1. As my van had a clock the electrical connector for the tacho is missing.
2. I have recently installed a Subaru conversion and have used the rjes front extension harness that has tacho feeds.
How do I wire all this up as the ribbon on my dash differs to the tacho one?
I know some people have done this but I don't know how
1987 VW T25: Subaru EJ20 using RJES parts (If it was meant to go fast it wouldn't be brick shaped!)
While I have a coffee... the VW tacho needs a resistor mod to correct its reading to suit the impulses coming from the Subaru ecu.
I posted a link ages ago, a google of "subaru vanagon tacho mod" should get you to it.
Sent from my Atari 7800
1985 Oettinger 3.2 Caravelle RHD syncro twin slider. SA Microbus bumpers, duplex winch system, ARC 7X15 period alloys
Thanks for your answer. I have seen the resistor MOD you are talking about but do you know how to actually wire in the tachometer as my dash ribbon is the one for the clock rather than the tachometer?
1987 VW T25: Subaru EJ20 using RJES parts (If it was meant to go fast it wouldn't be brick shaped!)
What age is the van?
I think later models had the wiring in already ( especially if you have the buzzer of doom dash. )
I have an '89 and all I originally did was remove my clocks and use the ribbon from the rev counter, but this wasn't on a Subaru conversion.
I think the solid green one on the 14pin plug - from memory - is the feed from the coil that drives the reading.
It only needs a 12v supply, and neg and that green feed from the coil to work.
If you have a late van with the solid green wire already in place from the coil, then all the hard work is done for you in respect to running wires.
So if you do have the green wire, you will just need to know where to connect it to the Subaru engine, and then do the resistor mod, and connect to the counter with a 12v and neg supply ( which would have been present for the clock on your van. )
In short, you will need to work out what you have already, then work from there. Different vans between ages will have different set-ups.
'89 1.9 DG
“Some people die at 25 years old, and are buried at 75 yrs old” ~ Benjamin Franklin.
If your dashpod foil is missing the tacho circuit, you could 'hardwire' the tacho, which has a row of 4 pins on the back. You could probably find some suitable terminals inside an old PC. The order of the pins is as follows, with the back of the tach toward you and the pins at top/left, working from left to right:
Earth
nc
Ignition
Engine speed signal (from coil or ECU)
There's an adjustment pot just below the connector, if you can get a computer on the Subaru ECU to check the actual revs, or maybe use a Gunsons box with a pickup on one of the plug leads to read the revs. Adjustment shouldn't really be needed but it's always nice to check things after an installaiton.
Syncrosport (taking a break as of summer 2024)
Volkswagen Transporter, reloaded.
Thanks guys. That's very helpful. I have a d reg formerly 1.9 water boxer. I will have a look for the green wire but thanks to your help it should be easy, especially with the eyes front harness. Also my van did have the buzzer of doom as it wentvoff an hour after buying the van, stranding me in Devon on the way back to the iom. Thank God for AA relay
1987 VW T25: Subaru EJ20 using RJES parts (If it was meant to go fast it wouldn't be brick shaped!)
Will the fuel gauge and water temp gauge work OK on the tachometer or will they also need fettling due to their different positions on the dash ribbon?
1987 VW T25: Subaru EJ20 using RJES parts (If it was meant to go fast it wouldn't be brick shaped!)
you need fuel and temp gauges specifically for the rev counter dash, they are a different size - the analogue clock dash ones won't fit. also you will need the rev counter pcb or will have to hardwire the gauges.
The foil for the instrument cluster really is the problem: it has been discontinued (and as Matthias from VW-Classicparts whome I asked about this told me, the original manufacturor VDO is not interested in producing a new batch for them as there are too many different versions and it would not be profitable for them). The options are to try and find a used foil, to try to solder up some solution or to buy an aftermarket replacement (I think Gowesty or one of the other US shops have come up with something but it is not cheap)
Cheers, André
'89 T3 GL syncro, 2.1 MV
'91 T3 doka syncro, 2.2 Subaru http://www.feine-tapeten.de" onclick="window.open(this.href);return false;
Also my van did have the buzzer of doom as it wentvoff an hour after buying the van, stranding me in Devon on the way back to the iom. Thank God for AA relay 
