Hi So some background: I have a -92 Vento GT 2.0 that was 1.8T swapped about 17 years ago which i bought last year after it had stood for about 10 years. Now everything(almost) is in good working order and I am down to this last thing I just can't seem to wrap my head around. First off i noticed the gas gauge was not working, this I have diagnosed to be a faulty cluster. The cluster with a faulty gas gauge is a motometer cluster. When i plug in either of the VDO clusters i have, gas gauge works and (almost) everything else as well. But on using either VDO clusters i get the "dead tacho and flashing oil light", however, it works while starting the car and dies almost immediately . If i plug the motometer one back in tach works perfect. The origin of one VDO i am not sure of, as it came in a box of parts with the car. The other VDO is from a mate who pulled it off his VR6 obd1, and it was working fine in his car. Are there differences between the motometer and VDO clusters? Is the rev feed different between models? What am I missing here?
check you have an earth to G1/5, often missed when loom is done. also make sure fuse 21 is ok, and you have ignition live fed to E/2 though if they power up and at least something happens when you switch on ignition its unlikely to be those
checked all fuses. Will check the connectors. Thank you. Any idea why the rev counter works on the motometer but not on the VDO?
when i took of the aux belt to look for a noise, the rev counter works when starting the car. Wth.. Edit; it Also works when i start the car with alternator plug off.
ok thats odd... i take it battery light comes on with ignition and goes out when started like it should? what engien code 20v is it, what alternator and does it have both pins wired up to the engine loom (look at the 2 or 4 pin plug on the starter end, see if both pins are wired up to something in main loom)
Yes, battery light works as it should, not if i disconnect the plug of course. It is an AGU. I would have to check the alternator, but i think it is the one belonging to the AGU. Both pins are wired at the alternator end, i'll trace the wires to see where they end up.
Ok with the agu you only need the battery light wire, 2nd pin is unused so whatever it's plugged into disconnect Later DBW use the 2nd pin DFM but doesn't affect running if disconnected, but if it was say a diesel alt with rev counter W pin output that might mess up ECU. Or if your MK4 alternator somehow got wired up like a MK3 diesel the signal output from the 2nd pin may be messing with the rev counter
So, I can try depinning #2 on the alternator, and that should make the rev counter work, and the alternator should still be charging?
Unfortunately it did not work. So i tried chucking the VDO gas gauge into the motometer, and that worked, seems to be reading low, but i wont really know that until i fill up. Anyway I would rather have a low reading gas gauge, than no gauge. To make it all nice and matching, i also swapped the other gauges, speedo is off by 20km/h ish, RPM is off by 100ish and temp seems to be reading a tad high I will just change everything back except the gas gauge for the time being. I have plenty of time to tackle the RPM counter problem during wintertime.