Troubleshooting Electrical Problems

[SVXMAN2001]

So over the years I've been able to fix mechanical issues on the svx, i.e. water pump, timing belt, radiator, suspension, a/c...etc.

I have not however developed an understanding of troubleshooting electrical issues. I've been pretty luck so far I suppose. However, now I am experiencing what is likely an electrical issue with my a/c system. As some may have read in my other thread I have replaced all components throughout the a/c system, pulled and held a vacuum however the system will not charge. Both the low and high side pressure readings are the same. I was told by the a/c technician that rebuilt my compressor that the likely source is a constant current to the relief valve (the svx manual indicates that the solenoid valve control controls the relief valve).

My problem is to troubleshoot it I need some sort of resistance guage. I have never used one although have seen technicians use it and it appears they stick the "nodes" in the wire to measure connectivity, current and resistance. I am uncertain as to whether there is a particular place to measure these readings...the manual indicates to measure a specific numbered terminals (again at a loss on this one). Does anyone have any suggestions on the type of "resistor" to buy? Again I apologize for my ignorance on this issue I'll continue researching in the meantime, thanks in advance. - Chris

[Tapani]

Is there a definition file for the A/C controller to be used with something like the ECUtuner?

This is a current topic for me too - my A/C quit producing cold last week even though the compressor runs. It's been fairly low performance thru the summer - even after recharging.

If someone knows exactly how the variable discharge compressor is controlled it would help a lot. My high side was a bit low and the low side kinda high - but it would be great to know how to force the compressor go on "full discharge".

Tapani

[Tapani]

http://www.phantomotaku.com/SVX/MSA5...3_Air_cond.pdf

Tapani

[longassname]

Tapani,

You can make your own definitions file to use the ECUtuner interface and software to perform diagnostics on your AC. I gave Phil Skuse, that's the guy with the gearshift map thread you posted in recently, the firmware from a select monitor cartridge a couple or few years ago and he pulled all the locations for all the select monitor functions off of it. I think he has a thread on that here somewhere. I just checked and see he has the locations for the AC diagnostics on his website here: http://www.alcyone.org.uk/ssm/aircon.html

I think he has the conversion formulas posted in the thread on the select monitor cartridge. His screenname here is B3lha

[Tapani]

Great, thanks a bunch.

I will look into it !

Tapani