I spent over 3 hours at a workshop the other day because my trailer had an ABS fault only when connected to the trailer. Fitter was convinced it was a trailer problem despite me telling him it occurs on multiple trailers. Conveniently if its a trailer problem its not their problem because my company use another place to fix the trailers.
Ended up pulling out because he didn’t know what was causing it and computer wasn’t picking up anything. Had this issue quite a few times now. Mechanics used to fix stuff and diagnose problems and repair stuff.
All I see fitters do is replace crap. Truck wont start? No problem we will replace anything and everything that may be causing it…
Soon as they have to use their brain to diagnose a problem though it all goes to crap.
Out of curiousity does anyone know why a DAF CF abs light comes on shortly after hooked up to a trailer. I had this problem before and someone explained the cause but I can’t remember. ABS still seems functionally just that the light is on. Pretty sure its a common problem or maybe I’m just unlucky.
Possibly, more likely to be a chaffing wire because the light activates when moving. Problem is I drive a prime mover with a drag so the loom is rather messy.
That being said with a prime mover its quite easy to attempt to clean the sensors as I just just drop the body so might give that a try.
Edit: Wouldn’t a faulty sensor cause the light to come on without a trailer though?
Edit now I see that it is drawbar trailers which you hook up to, so presumably the suzie belong to the trailer. In which case the socket on the back of the unit is likley to be suspect.
Could be may causes from dirt/ corrosion on a wheel speed sensor to a faulty modulator valve. An ECU/pump fault cant be ruled out either.
Simple and no cost options first would be to clean suzi connectors with electrical cleaner, same with the wheel speed sensors, plus while there check them for breaks/chafing ect.
IIt happened to me a few times, i was told the abs lead was not compatable with all trailers…so i changed the lead and everything was ok…seems to be different trailers have different settings…i didnt really understand the mechanics jargon…but it worked for me. btw, this was on dafs and carrier fridge trailers.
I changed the electrical leads and it fixed it. I can only assume that some of the sensor information runs through the main electricity lead As well.
Annoying how it was such an easy fix several fitters spent hours on the truck, without success.
Almost didn’t bother doing it as it seemed a long shot.
all the DAFs I have driven over the years have all had ABS warning lights come on,seems to be a common fault with these vehicles,our senior fitter said us drivers are not connecting them correctly,so he disconnects the ABS off my unit and put’s it back in and say’s it should be ok now,5 min down the road and I get the usual,EBS/ABS trailer not connected coming up on the dash,he put’s a new lead on and it still comes up on the dash after a time,doubt if it will ever be sorted,and mine’s a 66 plate
Brakes will still work fine though even with an abs fault. A warning light can be ignored, it’ll still be fine to drive back to the yard or until it can be looked at. Its not a breakdown/cant drive the truck issue…
truckman020:
all the DAFs I have driven over the years have all had ABS warning lights come on,seems to be a common fault with these vehicles,
I drive DAF CFs at a company with a fleet of over 600 trailers and it happens on just a handful, it is extremely rare to get one that does and that is including trailers that are thick end of 20 years old. It isn’t a common fault other than if you work at a company which doesn’t maintain their fleet properly.
lolipop:
Would have thought the obvious thing to do first was to change the lead or check the plug /socket connections
The ABS lead was changed straight away and all the fuses was checked along with cleaning the ABS socket. I assumed everything relevant to the ABS system ran through the ABS lead obviously the fitter assumed the same. Also there was nothing wrong with the electrical suszie it worked perfectly (aside from the abs error).
Fitter couldn’t work it out either and no one mentioned it on here as an obvious thing to do.
Fitter was adamant it was a trailer issue.
truckman020:
all the DAFs I have driven over the years have all had ABS warning lights come on,seems to be a common fault with these vehicles,
I drive DAF CFs at a company with a fleet of over 600 trailers and it happens on just a handful, it is extremely rare to get one that does and that is including trailers that are thick end of 20 years old. It isn’t a common fault other than if you work at a company which doesn’t maintain their fleet properly.
the ABS light stays off,just keep getting the warning every 5 min then it goes off,drives me mad
A problem you get quite often with newer trailers is the can hi and low data lines wont talk to the trailer.
Easiest way is to cut them out.Undo the end of the ABS suzi.Inside are 7 wires.
Red =ABS power
Brown = ABS ground
Yellow =ABS signal
Black =ABS sensing
White = ABS solenoids
Then you got a green/white tracer and a brown/white tracer.These are the data lines.
They are only thin and made of aluminium to cut down on electrical"noise" interference.
Just cut them off from the pins.
If the truck cannot sense a trailer EBS ecu it will just think its the old type trailer and just go into standard ABS mode.
