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Speed sensor?

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Old Feb 28, 2010 | 04:05 PM
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Default Speed sensor?

Hit a pothole with both driver's side wheels. My brake light is constant on and the Speedo doesn't work. Everything else does though (Temp, gas, RPM's) Friend told me it was my speed sensor? How would I go about checking for this and what to look for? And is it pretty straight forward to do?

If this is the wrong forum, please move mods. Thanks.
Old Feb 28, 2010 | 04:13 PM
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abs sensor is damaged prolly
Old Feb 28, 2010 | 04:18 PM
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How would I go about checking it?
Old Feb 28, 2010 | 04:24 PM
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if the wheel speed sensor was damaged, the ABS light would also be on because the ABS wouldn't be working anymore.
Old Feb 28, 2010 | 06:35 PM
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Actually my ABS and TPS lights are on as well. How many damn sensors do I have to check?
Old Feb 28, 2010 | 09:21 PM
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i would start with replacing the speed sensor. sometimes speed sensor can do weird things. actually i would start with disconnecting the battery for 20 minutes and see if that fixes it
Old Feb 28, 2010 | 10:11 PM
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Could anyone tell me where these sensors are located?
Old Mar 1, 2010 | 02:16 AM
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okay...you have, and get this now, 4 ABS wheel speed sensors. they are located in each wheel. their reading are used to determine your cars speed, and if the wheels are locking up under braking. then, on the 05-06 models, they are also used to determine if the tires are over/under inflated.

now, i think that if only one of your wheel speed sensors was bad, you're speedometer would still work since it has 3 other sensors to determine the cars speed. but if your ABS and TPMS and speedo are all broken, then i would guess that the either all your speed sensors are bad, or your ABS module has one bad.
Old Mar 1, 2010 | 07:40 AM
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im having the same problem...
i hit a bump today and my ABS light turned on... only that though =\
Old Mar 1, 2010 | 03:45 PM
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Originally Posted by draxcaliber
okay...you have, and get this now, 4 ABS wheel speed sensors. they are located in each wheel. their reading are used to determine your cars speed, and if the wheels are locking up under braking. then, on the 05-06 models, they are also used to determine if the tires are over/under inflated.

now, i think that if only one of your wheel speed sensors was bad, you're speedometer would still work since it has 3 other sensors to determine the cars speed. but if your ABS and TPMS and speedo are all broken, then i would guess that the either all your speed sensors are bad, or your ABS module has one bad.
So are the sensors actually on the wheel itself? For instance, let's say I take off my driver's side front wheel, would the sensor be off too? If so that could explain it because I bought another set of stock wheels and slapped those on.
Old Mar 1, 2010 | 03:47 PM
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And in the mean time can someone do me favor. What's your RPM when you're going:

2nd gear 20 mph
5th gear 45, 65, and 80 mph?

LOL thanks.
Old Mar 2, 2010 | 12:54 AM
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the tpms sensor is actually in the wheel. i know this because i used to work at a tire shop and have personally taken the tires off my wheels more than a few times and if im not mistaken(but ive been wrong before), the speed sensor is actually on the tranny. most cars if, if not all cars read vehicle speed from the tranny not the wheel itself. and i believe the abs sensor is inside the hat on the rotor. im not sure, i havent investigated it. but then again i could be completely wrong and im definitely NOT trying to discredit DRAX. im just telling you from my years of automotive experience.
Old Mar 2, 2010 | 03:44 AM
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Speed sensor are AC pulse generator, each wheel should have one, usually behind the brake rotor, it should be around the wheel bearing somewhere there, you should see two wires coming from it. disconnect each speed sensor and check the resistance value of the each speed sensor with a Digital multimeter, resistance value should around 560-680ohm. Not 100% sure that the value. I need to do more research on that value.

From what I see, you probably knock a connector loose. Best bet disconnect the battery and unplug the ABS control module wires harness connector(which is inside the engine compartment, should be near the coolant overflow tank) and wait couple of minutes and plug it back in and make sure it secure, and reconnect the battery, and see if it still show up. Then if it still does, then check the speed sensor as I wrote above.
Old Mar 2, 2010 | 04:09 AM
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Thanks for the help guys. I'll try all of those and see if it works.
Old Mar 2, 2010 | 05:26 AM
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Originally Posted by TunerKid
the tpms sensor is actually in the wheel. i know this because i used to work at a tire shop and have personally taken the tires off my wheels more than a few times and if im not mistaken(but ive been wrong before), the speed sensor is actually on the tranny. most cars if, if not all cars read vehicle speed from the tranny not the wheel itself. and i believe the abs sensor is inside the hat on the rotor. im not sure, i havent investigated it. but then again i could be completely wrong and im definitely NOT trying to discredit DRAX. im just telling you from my years of automotive experience.
i can respect that, but let me lay down a few facts for your.

the TPMS system on the 05-06 tC's use the ABS wheel speed sensors to determine if a tire is high or low on pressure, the 07 and newer have sensors in the tires themselves and thus the ABS and TPMS use separate sensors. the speedometer works off the ABS module, not the transmission, it determines speed based off the wheel speed sensors too.
Old Mar 2, 2010 | 05:28 AM
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^^ listen to drax.. he's providing the correct info.
Old Mar 2, 2010 | 12:33 PM
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i have 06 and 09 wheels and both have sensors inside them so what is inside of the 06 wheels then? and how could it read tire pressure from outside the wheel? again not trying to be a ____, just trying to understand! oh and sorry for the slight threadjack
Old Mar 2, 2010 | 01:53 PM
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Originally Posted by TunerKid
i have 06 and 09 wheels and both have sensors inside them so what is inside of the 06 wheels then? and how could it read tire pressure from outside the wheel? again not trying to be a ____, just trying to understand! oh and sorry for the slight threadjack
okay, the 05-06 tC's have TPMS, but it doesn't used sensors inside the wheels to measure tire pressure, instead, it reads and compares the speeds that the wheels are spinning at while you drive, and if there is a noticible difference in the number of revolutions between all the wheels, it assumes that atleast one of the wheels is over or under inflated, and triggers the warning light. it does this through the ABS wheel speed sensors.

the 07 and up tC's have actual TPMS pressure sensors in the wheels themselves. now, these sensors can be put in any wheel, so you could put a tire pressure sensor in the wheel from an 05-06 tC, it doesn't matter, the older tC's won't even know those sensors are there. but the newer tC's need those sensors to always be present and accounted for, or it will trigger the TPMS warning light.
Old Mar 4, 2010 | 03:55 AM
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Tried resetting my battery and the ABS harness but no luck. Now what I observed is that my mileage isn't moving at all. Sounds like the actual sensors now?
Old Mar 4, 2010 | 04:28 AM
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Originally Posted by GhostFaceKilla
Tried resetting my battery and the ABS harness but no luck. Now what I observed is that my mileage isn't moving at all. Sounds like the actual sensors now?

lol dont complain better for when u go to sell it
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