BrickBoard Archives
The files contained in this listing have been automatically archived from the active forums. Because the vast majority of posts are now in one place, this archive is considered legacy. You should use the SEARCH feature OR choose your topic and select date tabs within the forum you choose.
Is there a way to test the flywheel sensor?[200/89] posted by Carl on
Tuesday, 21 September 1999, at 7:42 p.m.
After reading various BB posts, I decided to find and remove my flywheel sensor. I called the local Volvo dealer and got a description and location, and after a soupcon of aggravation I had the thing in my hand. It has the yellow stripe, so it's the kind that can go bad, but externally it's in perfect condition. The cable and ends are pristine-looking.
Is there a way to test it with a multimeter, or better yet, fool the ECU by jumping the wires in its plug to find out if it is the reason my car won't start?
Please advise.
Carl Krall
Re: Is there a way to test the flywheel sensor?[200/89] posted by Steve Seekins on
Wednesday, 22 September 1999, at 8:25 a.m.
If your 89 has the OBD system with the black diagnostic connector under the hood, you can check for faults in the ignition system. Use A6 (test lead plugged into terminal #6), mode 1 (with ignition ON but engine not running, push test button for 1 second and release, then count flashes - sequence of 3 digits. Repeat until the first fault code shows up again. A 1-1-1 code indicates no stored faults)
Note that an intermittant problem or just weak signal from the crank position sensor may not set a fault code. The only way to really test the sensor is to check it with an O-scope and watch the signal response (pulse amplitude, width, and shape). The problem with the original sensors is that through design, they were weak and did not produce a strong signal - has nothing to do with how they look or visible wear. These parts are not particularly expensive - and having taken the old one out, you might be just as well off to install a new one rather than put the old one back in.
--Steve Seekins
Re: Is there a way to test the flywheel sensor?[200/89] posted by Ivan K. on
Wednesday, 22 September 1999, at 8:47 a.m.
The problem with these sensors is that they will only fail
intermittently. Usually, when they get hot.
This makes it hard to test.
They are cheap enough. Just replace it.
With high mileage cars, it's only a matter of time before
they fail. I had them fail on my Mazda, Plymouth, and Volvo 740.
Guess which one was the PITA to replace ?
Yes, you are right !
P.S. Flywheel sensor performs the same function as the Hall's sensor,
a.k.a. the "pick-up-coil", "ignition magnet", etc.