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Discussion Starter · #1 ·
So I started my car to pull it into my driveway and at certain points when I turned the wheel the brake pedal pulsated and the tcs light came on. Now Im pretty sure its the clock spring but I just wanted to be positive.
 

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Probably not. Clock spring is for Air bag/horn.

Probably a bad wheel sensor. When you turn, the wires are getting shorted or something.
 

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Discussion Starter · #4 ·
so could I just unplug the abs to temp solve the problem until I can get in there?
 

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Yes - but the TCS light or w/e will stay ON letting you know the system is not working. You could perform a visual of the ABS wires at the axles - you probably have a pinched wire or exposed wire which is shorting out (since it only acted a fool on a turn). Otherwise before you pull the plug on it - see if you can get a code pulled with an ISAT or TECH2.
 

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Discussion Starter · #7 ·
okay update

I pulled the main abs fuse and the car drove fine to and from an appointment I had but when I tried to brake so I could pull into a dunks the pedal was rock hard and I had to cost to a stop. I turned the car off and started it again and the pedal went right to the floor; so I pulled all the relays and the fuse and only then I had brakes so I could pull in to get a tow. I just got home from work now so I'm gonna play with it for a bit and see whats up
 

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When you pull the ABS fuses to the system it also stops powering the high pressure pump for brake assist (no vacuum booster, it's all through the accumulator), if you key it on and pop the fuses back in you will hear the pump run until the accumulator is charged back up.

The accumulator has enough reserve pressure for 10-20 stops (depends on condition of accumulator), then you get no more assist.

You could just unplug the wheel speed sensors themselves, they're the little round black 2-pin connectors, under the fishtank lid.

Best,
Drew
 

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Discussion Starter · #9 ·
okay that explains everything; in my searches I read that the sensors should be something like 12,000 ohms when the cars not moving correct? thanks
 

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Discussion Starter · #11 ·
another reason to just do alittle diag as opposed to that route - I keep forgetting about those damn nitrogen balls... I bet my c/v could used one as the ABS light is on for about a minute at start up then goes out... lol
...wat?
 

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Discussion Starter · #12 ·
okaayy I just went out and checked the resistance on the sensors...

drivers side was 1.123/4

passengers read 1.131

Took the car out with both unplugged and all seemed to be okay. Just for 100% clarification I can drive the car like this and have functioning brakes?
 

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Often times the sensors get dirty, which oddly enough case the ABS system at activate at low speeds. This was suggested by another TSL member when I was haying an odd low-speed ABS activation issue, and after cleaning the sensors the ABS worked perfectly again.
 

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Discussion Starter · #14 ·
Often times the sensors get dirty, which oddly enough case the ABS system at activate at low speeds. This was suggested by another TSL member when I was haying an odd low-speed ABS activation issue, and after cleaning the sensors the ABS worked perfectly again.
Thats the best news Ive heard all day; thanks :-D
 

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Took the car out with both unplugged and all seemed to be okay. Just for 100% clarification I can drive the car like this and have functioning brakes?
Yup. To test this theory, all you need to do to discharge the accumulator and make sure it pumps back up is:

1) Ignition off

2) Pump brake pedal firmly 15-20 times

3) Key ignition on, but don't start engine.

4) Listen for buzzing sound from high pressure ABS pump running, it should run 15-20 seconds and then shut itself off once the accumulator pressure reaches it's prescribed pressure.

You should be able to hear the pump under the hood, and you should feel a little vibration in the brake pedal while the pump is running, it's really obvious.
 

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Discussion Starter · #16 ·
Yup. To test this theory, all you need to do to discharge the accumulator and make sure it pumps back up is:

1) Ignition off

2) Pump brake pedal firmly 15-20 times

3) Key ignition on, but don't start engine.

4) Listen for buzzing sound from high pressure ABS pump running, it should run 15-20 seconds and then shut itself off once the accumulator pressure reaches it's prescribed pressure.

You should be able to hear the pump under the hood, and you should feel a little vibration in the brake pedal while the pump is running, it's really obvious.
Just went out and followed the steps and it did exactly what you described;

Big thank you to all you guys for the help; much appreciated
 
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