Code C1241 for ABS on an Early '99

imelmo

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Having a brake issue on our early '99 Superduty (my first diesel actually :D ). The employee that was driving the truck said he had to brake hard in a curve and after he did the ABS light came on and now whenever you hit the brakes they pulse real bad.

I hooked AE to it and it gives a code C1241 (ABS Hydraulic Pressure Differential Switch Input Circuit Failure).

Not finding a whole lot of info on it. The little I did find seems to be saying the RABS valve (rear ABS valve) needs to be replaced.

I can't find anything showing where this is, what it looks like, or a part number or anything to order one.

Can someone point me in the right direction? Is there something else I should be looking at?

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co04cobra

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I believe it’s all integrated into the ABS module itself. The abs module is bolted to the rad support behind the LH headlight.
 

DieselDC

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Replace the abs unit up front as stated. Just old and worn.


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imelmo

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Any earthly idea of a part number or brand for a replacement? Ford no longer carries them and I can not find a replacement anywhere.

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DieselDC

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No part #. Look on Ebay and it will tell you the year it will fit. Look at yours and see how many tubes running to it and buy one exactly like it. Some are only 2w abs while others are 4w abs. Obviously the 4w abs will have two extra tubes running to it. I replaced a few and 99-03 works fine. That same module is on other models as well.


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DieselDC

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eb86f33cb72700dfcfedc34f12878f1f.jpg


One of my trucks. 6 túbes. Sorry can’t help more than that (part # not visible)


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Tommikaze

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An update for people searching for a repair to the C1241 ABS code on Ford trucks (1999 F-350 with rear wheel ABS in my case).

I had to slam on the brakes to stop for an emergency vehicle passing. The ABS fired during this stop and the ABS light immediately came on. I cycled the key and the light stayed on. Connected a scanner when I got home and found the C1241 code. Searching the internet didn’t give much info beside this post and a couple others. Those posts suggest replacing the “ABS Module” behind the LH headlight. The problem is that part is not available so you have to get it from a junkyard or EBay (if one is even available).

Since the ABS firing is what caused the code I decided to play around with the ABS braking to see if I could figure out what made it throw the code. I cleared the code but it would come right back on if I cycled the ignition. If I cleared it after the truck was running I could drive about 3 miles before the light came back on and threw the same ABS code.

I decided to make the ABS fire during the time the light was off (ABS won’t work if the light is on). I did this by slamming on the brakes at low speed (about 20-25mph). You can also do it in gravel because that makes the ABS fire easier. I did it until the ABS light came back on (about 3-4 times). I cycled the ignition, cleared the code and made the ABS fire one more time. The ABS light did not come on and when I cycled the ignition it did not automatically throw the C1241 ABS code like it had been doing.

I’m pretty sure what happened is the valve assemblies in the ABS hydraulic unit were getting stuck because the ABS doesn’t fire very often. When I did have to use it the valve stuck causing the code. By forcing the ABS to fire it worked the valves until the freed up and stopped causing the fault that creates code C1241.

I hope this post helps someone with this code and saves them buying parts. My truck has been fine. No ABS light since the last time I got to the ABS to fire and free up the valving in the hydraulic assembly.
 

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