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DaCan23
04-22-2005, 01:53 PM
Using a voltmeter or something?

Garlic Breath
04-22-2005, 08:25 PM
Bench testing requires a power supply and a multimeter with the capability of measuring continuity or ohms.

MTRIPLE
04-22-2005, 09:22 PM
9 volt battery works for me....

eligunn
04-23-2005, 08:48 AM
you can check it while it's in the car I think.
The Bentley manual has the procedure for checking the dme relay.
If you've got a wiring diagram it helps.

Bill R.
04-23-2005, 09:14 AM
across the currenty carrying side with an ohmeter for continuity but that won't tell you whether it will carry the current load needed, you can have arced contacts that will show continuity but won't carry a higher amp load.
I would open it up if you suspect its not working and visually inspect the contact points for arcing or burning If they are clean then you can apply voltage to the coil and watch the points close.




Using a voltmeter or something?

Jon K
04-23-2005, 01:56 PM
Using a voltmeter or something?



Seeing as Parts Express has Bosch 30A relays for like $0.60 ea, i don't know why you'd even bother!

ryan roopnarine
04-23-2005, 02:07 PM
Seeing as Parts Express has Bosch 30A relays for like $0.60 ea, i don't know why you'd even bother!


um, i doubt they're talking about garden variety relays one can get from radio shack/napa, et cetera. the abs module has two relays on it, each are about $40 from bma. there are several relays that might be worth testing in an e34, ie cost at least $10 for replacment. i thought you needed 12v to get a legit check of a relay, if 9v will do it, ill start doing things that way.

Javier
04-23-2005, 02:21 PM
pick up at 75% of nominal voltage. So not working at 9 Vdc will not tell you for sure it's bad.

Javier