Markharrison2 Posted September 17, 2016 Share Posted September 17, 2016 ok would appreciate some help. Have had intermittent issues with revs counter dropping down to zero when still driving, found a loose earth, thought it was fixed. Then got a dashboard fuse blown when driving, replaced it, was ok, next time out same thing, except it blew the replacement fuse straight away. Figure had a short, have searched but not found anything in the maze of wires under dash. stuck in another fuse, turned heater off (on same fuse as dash), this time didn't blow, dash fired up, tachometer appeared to work and did normal recall of highest rpm from last drive) but tachometer and ACES both stuck at 2000 when aces fired up.any ideas? Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted September 17, 2016 Member Share Posted September 17, 2016 Who fitted the ACES unit, and how long ago?Can you see where it gets its engine speed signal: wired from the tachometer terminal or spliced into the signal wire to the tachometer or further upstream?If you can find that try disconnecting it and seeing if the tachometer behaves normally....What type of dash and tachometer?Does it now drop to 0 when the ignition is turned off, or does it stay at 2,000 rpm?Fan now working normally?All other instruments OK?...Do you have a wiring diagram and a multimeter?Jonathan Link to comment Share on other sites More sharing options...
Markharrison2 Posted September 17, 2016 Author Share Posted September 17, 2016 ACES fitted in2008 by original owner/builder. Will go back into garage and have another dig around thanks for suggestions.yes have multimeter. Have the wiring diagram from original assembly guide.it was originally built as a 2006 roadsport SV K-series, not sure on dash type.thanks Link to comment Share on other sites More sharing options...
Markharrison2 Posted September 17, 2016 Author Share Posted September 17, 2016 Ok with ACES disconnected, everything works normally. Tachometer drops to zero when ignition off. Will investigate where it splices into Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted September 17, 2016 Member Share Posted September 17, 2016 Progress. :-)It never occurred to me to disconnect at the ACES end! But did you disconnect everything or only the signal wire? Jonathan Link to comment Share on other sites More sharing options...
Markharrison2 Posted September 17, 2016 Author Share Posted September 17, 2016 Tachometer is Caterham unit, reads up to 8k.fan not working after 1-2mins running, is that normal? Link to comment Share on other sites More sharing options...
Markharrison2 Posted September 17, 2016 Author Share Posted September 17, 2016 disconnected both aces leads Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted September 17, 2016 Member Share Posted September 17, 2016 ...fan not working after 1-2mins running, is that normal?I meant the heater fan, following your comment about the heater, not the radiator fan... Jonathan Link to comment Share on other sites More sharing options...
Markharrison2 Posted September 17, 2016 Author Share Posted September 17, 2016 Ok aces splices into black and white wire that goes into back of tachometer Link to comment Share on other sites More sharing options...
Markharrison2 Posted September 17, 2016 Author Share Posted September 17, 2016 so with aces change lights disconnected, everything works including aces box. But fan still not moved.thoughts? Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted September 17, 2016 Member Share Posted September 17, 2016 Now that the tachometer is working properly we need to work out if the fault was inside the ACES unit or in the external wiring.I don't know anything about these: have you got any instructions we can look at?Jonathan Link to comment Share on other sites More sharing options...
green george Posted September 18, 2016 Share Posted September 18, 2016 With regard to the ACES unit this may help:http://www.aceserve.co.uk/new04/userguidess.html Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted September 19, 2016 Member Share Posted September 19, 2016 I don't know enough about the ACES units to advise on how to debug them.But following from the tachometer now working I'd be trying something like the following, testing that it still works and that no fuses have blown etc after each step: ACES units unpowered. ACES units powered. ACES units powered and a new temporary feed from the tachometer terminal to the ACES input. ACES units powered and the original feed reconnected.Jonathan Link to comment Share on other sites More sharing options...
Markharrison2 Posted September 19, 2016 Author Share Posted September 19, 2016 Instructions for sure shift 2 as I have. http://www.aceserve.co.uk/new04/pdfs/ss2ug5d.pdfMy plan is to check wiring carefully at some point, if that is ok, has to be the box, for that will contact the aces technical support , so will get to the bottom of it with that. Glad we narrowed it down, and I can still use the car in the meantime! Thanks Link to comment Share on other sites More sharing options...
Markharrison2 Posted September 19, 2016 Author Share Posted September 19, 2016 Didn't show your latest post when I looked for some reason, will try your suggestions Jonathan, thanks Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted October 2, 2016 Member Share Posted October 2, 2016 How's it going?Jonathan Link to comment Share on other sites More sharing options...
Markharrison2 Posted October 5, 2016 Author Share Posted October 5, 2016 Hi, have been busy with other things, hopefully get a look this weekend. Got some useful advice from aces technical support: Sorry you have been having problems with the SureShift 2. This sounds like a short circuit on the signal wire. Do you know if it was shortened at any time? It is of a co-axial construction (like an aerial lead) with the outer connected to ground via the plug. The outer must not come into contact with the inner otherwise it will cause a short circuit of the signal which would result in no RPM being seen by it or any other tachometer device connected to the same signal. If you unplug the power lead from the SureShift 2 box and disconnect the signal end, you can test for continuity between the signal end (1/4 inch female spade) and the body of the plug. If there is a short here, it is most likely to occur if someone reduced the length of the cable and did not keep the outer away from the inner. It is possible for a short to occur at the plug end if the insulation between inner and outer is damaged. If you find a short circuit there, you may be able to reterminate it yourself or return the power loom to us for repair. Will look into this when get a chance. Thanks Johnathan, Mark Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted October 6, 2016 Member Share Posted October 6, 2016 That makes sense. Suggestion 3 in post #13 might not be possible without some widgets. But testing for the short sounds good. I've never seen that cable/ subloom: can you unclip it and add a photo?Jonathan Link to comment Share on other sites More sharing options...
Markharrison2 Posted July 14, 2017 Author Share Posted July 14, 2017 Ok you guys deserve an answer on this after all the helpful suggestions you gave me. I ended up getting an auto electrician to help. He traced it to a poorly installed water/oil temp gauge, that was shorting to earth and blowing the dash fuses. When I disconnected the aces computer, it altered this connection temporarily leading to confusion. Once rewired was ok. Also had to loosen the wiring on the sprung loaded fuse to the aces as it was so tight it was preventing the circuit to complete. Cheers Link to comment Share on other sites More sharing options...
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