testing wheel speed sensors w/ mulitmeter
04-15-2011, 06:12 AM
#1
testing wheel speed sensors w/ mulitmeter car is 99ws6 110K miles
the ABS sys has been intermitantly malfunctioning (ABS,brake lights up on dash) I removed the rear wheel speed sensors and they where covered w/ brake pad particals, cleaned then off w/ a clean cloth lights on dash dissappeared now are back.
second fix was to replace one of the blow taillight bulbs in third taillight that did'nt last to long maybe a week.
I would like to test my wheel speed sensors. I am thinking they operate off of resistance.
like if car is stopped sensor is sending 0 ohms to ECM when car is in motion sensor starts increasing the amount of resistance so the ECM can now calculate.
My ? w/ wheel off ground can I spin the wheel and mearsure the resistance
I'm thinking the faster the wheel spins the higher the resistance then when wheel stops resistance should go back to 0.
? is this the proceedure for testing wheel speed sensors?
I am one step away from sending my ABS brake control modules relay section out for a rebuild.
edit I have read that the rear WSS are usalley the problem I haven't removed and inspected the front yet.
Thanks for any helpfull advice
the ABS sys has been intermitantly malfunctioning (ABS,brake lights up on dash) I removed the rear wheel speed sensors and they where covered w/ brake pad particals, cleaned then off w/ a clean cloth lights on dash dissappeared now are back.
second fix was to replace one of the blow taillight bulbs in third taillight that did'nt last to long maybe a week.
I would like to test my wheel speed sensors. I am thinking they operate off of resistance.
like if car is stopped sensor is sending 0 ohms to ECM when car is in motion sensor starts increasing the amount of resistance so the ECM can now calculate.
My ? w/ wheel off ground can I spin the wheel and mearsure the resistance
I'm thinking the faster the wheel spins the higher the resistance then when wheel stops resistance should go back to 0.
? is this the proceedure for testing wheel speed sensors?
I am one step away from sending my ABS brake control modules relay section out for a rebuild.
edit I have read that the rear WSS are usalley the problem I haven't removed and inspected the front yet.
Thanks for any helpfull advice
Last edited by badmfkr; 04-15-2011 at 06:18 AM.
04-16-2011, 12:23 PM
#2
Whenever I want to find out how a sensor works and how to test it, I go to the Wells Counterpoint articles. They are great! Here is the one for ABS sensors: http://www.wellsve.com/sft503/counterp_v11_i4_2007.pdf
Looks like they use a rotating magnet and create a waveform. They definitely don't go off of resistance like a non-rotating sensor. In order to test, you'll need special equipment. For the fronts, I'd expect that you'll have to replace the hub/bearings way before the sensor will go bad on you.
Looks like they use a rotating magnet and create a waveform. They definitely don't go off of resistance like a non-rotating sensor. In order to test, you'll need special equipment. For the fronts, I'd expect that you'll have to replace the hub/bearings way before the sensor will go bad on you.
04-16-2011, 01:06 PM
#3
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Interestingly I have this problem too. Car only has 35000 MI. I ohm checked all four. The front ones are close and the rear are close to the same value, but different. Can't remember what they were right now. No codes in ECM either.Hmmmm
04-18-2011, 01:17 PM
#4
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about a foot or two into the wire from the speed sensor is another connector, four prong gray i think (at least these are in the rear, cant remember the fronts), which connects it to the body and back to where ever... these were dirty on mine and gave me the same lights, and are right around the inner wheel. maf cleaner works great too to get down in there...
10-27-2011, 09:32 AM
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I still have this problem, funny thing is, the lights only come on when I drive in 5th or 6th gear for any amount of time. Never 1-4th. Anybody got the rear sensor part numbers?
10-28-2011, 04:17 AM
#8
Whenever I want to find out how a sensor works and how to test it, I go to the Wells Counterpoint articles. They are great! Here is the one for ABS sensors: http://www.wellsve.com/sft503/counterp_v11_i4_2007.pdfI'll read up on this artical Thanks
Looks like they use a rotating magnet and create a waveform. They definitely don't go off of resistance like a non-rotating sensor. In order to test, you'll need special equipment. For the fronts, I'd expect that you'll have to replace the hub/bearings way before the sensor will go bad on you.
Looks like they use a rotating magnet and create a waveform. They definitely don't go off of resistance like a non-rotating sensor. In order to test, you'll need special equipment. For the fronts, I'd expect that you'll have to replace the hub/bearings way before the sensor will go bad on you.
about a foot or two into the wire from the speed sensor is another connector, four prong gray i think (at least these are in the rear, cant remember the fronts), which connects it to the body and back to where ever... these were dirty on mine and gave me the same lights, and are right around the inner wheel. maf cleaner works great too to get down in there...
yes my car has TSC.
edit I have decided instead of rebuilding the ABS Electronic module for $160. I will eventualley just complely remove the intire ABS sys.
Thanks Guy's for feedback
01-23-2012, 02:23 PM
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The MWC housing is huge and requires you to shave some of plastic off the sensor in order for it to slide into the hole. I had appearently forced one in during the axle swap and damaged the sensor. I ended up replacing one of the sensors to correct the problem. No light sense then.
