Fault Tracing for 00533 (Idle Speed Regulation) 19-00 (Lower Limit).

Hi, I need an opinionon this (deep breath needed I'm afraid!).


I started investigating an idle fault on this petrol 1.6 AKL engine Golf 1998 – revs would fluctuate from start around 100-200 above base idle. An original fault logged was cam sensor (no signal), and having swapped out that,it now shows a fault as in the title. I've read Crasher's response on this sort of query to previous questions, and I've followed the advice given, namely to firstly try throttle body alignment in group 098, and when that didn't resolve the problem, to try Adaptation 10 for Group 00, reading and saving the values three times, followed by another TBA – but the problem still didnt resolve. (EDIT: Just to add that the TBA is apparently successful - the zone 4 value is briefly shown as 01 before becoming 00, so presumably normal?)

However, I then noticed the Operating Conditions in 098 show 00000100, (here:

http://i1261.photobucket.com/albums/...psfmjfe7mb.jpg

which, according to the Workshop Manuals Online resource suggests “Nocurrent supply to throttle valve control”. The Manual reference is here: http://workshop-manuals.com/volkswagen/golf-mk4/power_unit/simos_injection_and_ignition_system/mixture_preparation_system_electronic_inj.gas/checking_components/checking_throttle_valve_control_part/
and a screenshot is here:

http://i1261.photobucket.com/albums/...ps3cr359b7.jpg


This is where I start to get confused - I've checked the voltages at the throttle valve control part as per the schematic above, and find voltage on pin 4, but nothing on pin 7, so according to the Workshopmanual reference there is a fault with the ecu (I've checked continuity between the brown/blue wire coming out of the ecu to pin 7of the plug). However, I looked further at the circuit flow diagrams (here:

http://i1261.photobucket.com/albums/...psjymrdqxr.jpg


and the brown/blue wire appears to have a common ground point at item number 220. So if this is a ground, this appears to contradict the manual reference check asking for a voltage check at pin 7? The other thing I notice is that my wires are not connected to the same ecu sockets as the manual reference (my brown/blue goes to something like pin 101 – a long way from the socket 70 that the manual specifies –duh?)

So in short, is the workshop manual reference correct, or is there a better reference to check out the current supply to the throttle valve?
Any light that you shed on this will be much appreciated! Thanks Joe