ABS light

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Apr 13, 2010 | 12:41 PM

justin_pistol

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ABS light

hello all,

Maybe someone could help me out a little here, you guys have soooo helped me out in the past

THANKS

TRUCK- 1997 F-150 4x4 5.4L 180,000 miles ( great truck )

ok. The ABS light came on yesterday and wont go off.

I did a search and read of some other guys with same problem so I checked all the wires I could see from under thr truck (looked good)

Then I replaced the rear diff abs sensor ($13.99 autozone special) no help. The omhs on the old one was 1200 and i guess that is in range.

The light comes on when I start along with the 4x4 and low range light the 4x4 and low light go off and ABS flickers and comes right back with the truck still in park.

Where are the front wheel sensors and how hard are they to get at? Can they be tested , fixed, or replaced from a junkyard? Autozone wanted something like $169.00 for one.

Thanks in advance for and advice or information, you guys rock

Apr 13, 2010 | 06:24 PM

Ultramagdan

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From: Kansas

I would have a ABS code reader put on it first. It will keep you from chasing parts.

Apr 14, 2010 | 08:43 AM

justin_pistol

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where would I find a abs code reader? and does it plug into the same port the regular code readers?

Thanks justin

brakes work fine its just the light being on all the time sucks. Right now everything on the truck works like new and I dont want to start letting things go.

Apr 14, 2010 | 10:41 AM

Ron W.

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From: Stockton Ca.

The better ( read more expensive ) scan tools will read ABS, SRS and trans codes, how ever if you're looking for a cheaper one like I was google " autel us703 " got mine for $156 through amazon.
And yes it plugs into the same port.

Oh and I'm sure there are other brands out there that will do the job as well or better.

Apr 14, 2010 | 03:15 PM

xxl_2321

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the front sensors are on top of the hub bearing assembly rite behind the the brake rotor shield. they are held on by one allen head bolt

Apr 14, 2010 | 04:03 PM

justin_pistol

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ok I got a cool dude at a repair shop to read my codes

C1155 LF speed sensor input circuit

C1185 ABS power relay output

any ideas were to go from here???

I'm thinking check the relay first because easyer to get to

could a bad relay cause a speed sensor failure code? (fingers crossed)

any input would be great

ok I looked for the ABS power relay and all I found in the fuse box was a 5A fuse ( good) to 4WABS module and relay.

then I looked in the power dist box and all I found was 60A fuse (good) to 4WABS/rear anti-lock and a diode for rear ABS.

I can't find the ABS power relay.....can someone help me here?

Chilton says "the control unit for RABS is located in the dash" and " the control unit on 4WABS is called Eelctronic hydro control unit (EHCU) is located inside the engine compartment"

Can someone tell me were this thing is?

My truck coded :ABS power relay output: is this what it is refering to?

ok, can't find the relay so lets check out the LF speed sensor.

I pulled the wire conector to the LF senor inside the engine compartment and tested ohms....open circuit.

Is this the cause of my ABS light staying on?

Last edited by justin_pistol; Apr 14, 2010 at 05:22 PM. Reason: update