123jamesrob 10 Posted September 12, 2018 Hi guys, Having issues with my speedo not working, all my other gauges i.e fuel, rpm etc is working. I'm getting no speed on the needle and no MPG or distance. Good for the mileage not great for anything else :smug: I've up to now replaced the widget in the gearbox, the sensor on top of the gearbox, tested the plug to see if there is power getting to it upon the ignition being on, checked that the thing is spinning when in the gearbox, checked all the connnections at the back of the clocks, even changed the clocks to a different set to see if that would solve it, honestly at odds end with it. Any advice would be massively appreciated, cheers James. Oh, I noticed a post about the ISV affecting the speedometer, is this a possibility as mine is running rough at the minute and the ISV is my main culprit I think, I've got one on route a the minute hoping that will resolve the rough tick over. Ta.:thumbleft::thumbleft::thumbleft: Quote Share this post Link to post Share on other sites
vw rule 19 Posted September 14, 2018 Hello there, the idle stabiliser valve (ISV) should vibrate / hum slightly when your engine is running, according to the Bentley manual for the 9A engine, If you think the (ISV) isn't working you can test it with a multimeter. ***(With 3 wire connector plug)*** With the ignition switched on, you should have 12v from the centre terminal in the plug, and approx 10v from the two outer terminals. Also you can check to see if the (ISV) it's self has continuity or not, by checking the resistance between the centre terminal and each of the outer terminals, if you don't have any continuity then the (ISV) must be dead. **(With 2 wire connector plug)** With the ignition switched on, you should have 12v from terminal 2 in the connector plug, also you can check continuity between the 2 terminals on the (ISV) if you don't see any on your multimeter then the (ISV) is dead. The (ISV) and (Cold start valve) on the MK2 Golf 16v / Corrado 16v with engine code 9A looks like the fuse for it is number 15 = (10amp fuse) Multi function indicator is fuse 16 (15amp) Also I think the MFI uses a vacuum to measure the volume i.e the amount of cylinder capacity usage to determine MPG or something like that, I think there's a sensor on the back of the instrument cluster, where a vacuum hose is connected which then goes through bulkhead and connects to the brake servo hose, right on or next to the one way valve which is plumbed into brake servo pipe behind inlet manifold. If the vacuum hose isn't connected or split then you won't receive / see any MPG readings from your MFI. Most of the time it's the vehicle speed sensor (VSS) which is at fault, when your electronic speedo isn't working. This sensor is attached to gearbox above the differential and connects to the speedo gear. But you've said that you tried a different sensor and had no joy. And you said you've tried a different instrument cluster. Sounds to me like you're not getting a signal from the VSS wheather that's a wiring fault or faulty sensor. Just seems strange how you've tried different parts and it's still not working. In theory you should be able to unscrew the VSS with the connector plug still attached, and turn the spindle drive within sensor you should see the speedo move, other then that it'll be a wiring problem possibly. The VSS plug has 3 wires, Power, Signal, Earth If you've got power and earth then it's got to be the signal wire that's at fault ? I'll have a look at the Bentley manual tomorrow after work and see what I can find. Si Quote Share this post Link to post Share on other sites
123jamesrob 10 Posted July 27, 2019 Hiya mate still got this issue, there’s 5 volts getting to the white and blue wire in to the VSS. Got earth no power coming to/from the other wire. Any ideas? Thanks Quote Share this post Link to post Share on other sites
smig 1 Posted July 27, 2019 Go to your fuse box and check fuse 15 Quote Share this post Link to post Share on other sites
123jamesrob 10 Posted July 28, 2019 Sorted! Thanks very much Quote Share this post Link to post Share on other sites
Cressa 44 Posted July 28, 2019 Was it the fuse? Glad you have sorted it. Apologies that I have a VR so couldn't help, but always glad of a happy Corrado ending Quote Share this post Link to post Share on other sites
123jamesrob 10 Posted July 28, 2019 Was it the fuse? Glad you have sorted it. Apologies that I have a VR so couldn't help, but always glad of a happy Corrado ending It was, honestly didn’t think to check it as I thought the whole of the instrument wouldn’t have worked if the fuse had gone. What a nightmare haha Quote Share this post Link to post Share on other sites
vw rule 19 Posted August 2, 2019 Good to hear you got it sorted, I've tried to reply to this thread but haven't been able to due to a error / block on this forum, apparently other members on this forum are having similar problems. Si Quote Share this post Link to post Share on other sites