Enyar
Dork
6/30/15 9:04 a.m.
Thought I had a good one but apparently not. The damn A/C on my VW stopped owrking and all the tests I've tried have passed with flying colors except those related to duty cycle. Looks like I need to buy a better multimeter.
Any recommendations?
Off topic- should I start a thread here for the A/C troubleshoooting? TDIclub and vortex has run out of ideas but you guys always seem to come up with something clever...
RossD
PowerDork
6/30/15 9:07 a.m.
An oscilloscope is a great tool if you have some money and the space to keep them around. Used ones on CL, or a cheap sound card and free software can get you going. You'll need a voltage divider to keep it from frying your sound card. Do some research on the sound card o-scope.
A Fluke 87 is kind of the gold standard, but it's priced like Snap-On. Mine has been going solid for more nearly 15 years though.
If you can find one that someone is getting rid of because the display has faded at a good price (their mistake), that's a known problem you can repair yourself cheap with this kit--
http://shop.flukerepairkit.com/
NOHOME
UltraDork
6/30/15 9:45 a.m.
Missing how this is related to the meter? What are you trying to observe?
Used Fluke, anything will do, check around on CL, should be able to score one for $50 or less if you're patient.
Not sure what you mean by whatever you have not being good enough though. A HF freebie is good enough for virtually all automotive work.
Enyar
Dork
6/30/15 2:37 p.m.
NOHOME wrote:
Missing how this is related to the meter? What are you trying to observe?
Hell if I know, I've never been great with these things. I need to measure duty cycle to test some sensors and best I can tell, my multimeter can't do that.
RossD
PowerDork
6/30/15 2:39 p.m.
can a dwell meter be used for duty cycle?
NOHOME
UltraDork
6/30/15 3:48 p.m.
Enyar wrote:
NOHOME wrote:
Missing how this is related to the meter? What are you trying to observe?
Hell if I know, I've never been great with these things. I need to measure duty cycle to test some sensors and best I can tell, my multimeter can't do that.
"....Check for voltage to the compressor clutch via pin T14/10. If voltage is present proceed with clutch and/or wiring diagnosis. If a pulsed voltage is present, look for a shorted compressor clutch."
If this is the test that you have trouble with, then I see the issue: Digital meters are not good at picking up a pulse. One of the cheap probes that looks like a screwdriver with a point would work better for such work. (Or a light-bulb and some wire)
In reply to RossD:
I use one of these and have been happy with it. Will measure dwell, duty cycle, pulse width, rpm, all handy for auto diagnosis and more challenging to do with a standard home multimeter.
http://www.esitest.com/590TRMS.html
EvanR
Dork
6/30/15 5:00 p.m.
/begin: grumpyoldguy
You young kids today! You wanna find electrical pulses? Go look in your grampa's tool box. I still have one of these, and you should too!
/end: grumpyoldguy