Hey All, I have a 2003 F250 SD XLT 4x4 5.4L V8 Super crew cab. And I have a abs light on. I also have a snap on Ethos plus scanner and scanned the truck and found these two codes. The code are as follows: C1185 ABS Power Relay Circuit Fault Now let me give you guys some back ground on this truck. About a month ago, I had to have the driver side front differential replace due to faulty hub locks. Also had the brake lines replaced also due to rusting issues. But then when I got the truck back the ABS light would go on and while driving. Now my driver front brakes are bad only the driver front... And I now I'm wondering if the speed sensors are bad as well cause I had a code come up for that but can't remember what the code is. I tried to rescan for it but it doesn't come up??? Also it would be great if you guys could tell me where this stuff is on the truck so that I can do the job myself. The guy I took it to must have not done the job right, cause it wasn't like this before I gave it to him. I really could use your guys help on this!!

 

can anyone tell me where the abs relay is in the truck to replace it?

 

 

where is the relay located?

 

 

I looked and the manual shows nothing

 

 

 

 

I've only had my ABS light come on once and it was a failed sensor (in the hub).

 

 

when I put my scanner on it and it came back circuit failure at relay. So do you think I need to replace the whole module?

 

on the driver side the sensor was replaced

 

Don't know if you fixed your truck, but I'm going through this on my '02 right now.. Found several "troubleshooting" guides that apply to several different years of SuperDuty. Dunno if this is the same for your '03, but it stands to reason the designs didn't change much at all between '02 and '03.

Check fuses F2.25 (10A) and F2.66 (60A - This one will possibly be labeled 602 - mine was) Both of these fuses were good on my truck.

Check power at the ABS module connector. Module is in the left front of the engine bay under the air intake and evaporator canister. If your truck is like mine, you'll need to remove both and unbolt the brackets holding the ABS pump/Module assembly in to get access to the wiring harness connectors. (Whoever the engineer was that decided to put the connectors in the most inaccessible location possible should be flogged.)

Grab a multimeter and check for battery voltage full time on Orange/Yellow wires at pins 9 and 25 from fuse F2.66
Check Tan/Red wire at pin 16, should be hot when key is ON - fuse F2.25
Check for continuity between Ground (G105 specifically - dunno where that is, but on my truck, there's a LG/YE ground on the core support right above the driver's side headlight.) and the Light Green/Yellow wires at pins 8 and 24.

I'll be doing the above checks in the morning. Ran out of daylight after work today.

A couple of the other sites revealed broken wires near various connectors and the fix was to replace the entire wire, or cut it back to good copper and splice in a good piece. I also found a reference where a failing battery wasn't delivering proper voltage to the ABS module and would trigger the light on occasion. I just replaced my 5 year old battery but am still going to see if I can find any issues just in case.

 

Pulled the ABS module out and checked the connector. All the tests were correct per the info I found above. Reassembled and started the truck. No ABS light. I'll have to take it to my mech and ask him to check for codes again as my cheap POS scanner didn't see any of the three ABS related codes he found.