Daf Brake Warning Light

Matafleur

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I had my lorry serviced and thoroughly checked over 3 weeks ago, I had it back for a couple of days after that and during that time I had a brake warning light come on whenever I applied the brake or handbrake, it went off immediately the brake was released. I took it back to the garage and on the way there the brakes were binding. They diagnosed a master cylinder issue and it has subsequently had new brakes and pads, master cylinder, servo, and brake pipes, as well as any work advised after the service.

But the warning light still comes on when I brake! I picked it up late on Friday so didn't get chance to ask them about it. Obviously I will call them on Tuesday but in the meantime has anyone experienced this? It's a W reg so an older vehicle.

Thanks in advance
 

Red-1

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If it is a red light I would not use it until it is sorted. I would be a bit annoyed that the garage had not done a test drive to realise it was not fixed.

If it is an amber light I would use it this weekend, but take it back on Tuesday.

In answer to your question, "Has anyone experienced this?" Yes! I bought a lorry that was in the economy bracket, and when I test drove it the red brake light came on whenever the brakes were used. The owner told me that, "It shows that the brakes are working!" Ha Ha. This was a well known seller too, not a hapless private owner.

It was cheap enough so I bought it. The air tanks showed enough pressure, even with the light on. I am sorry, I can't remember what was the issue, but it was not expensive to fix, and it was not the XXXX cylinder as that was replaced about 6 months later when it sprung a leak (I AM a hapless private owner!).

If I had to guess what it was I have a feeling it was the compressor??? Not building pressure up quickly enough??? But I am not at all sure as the air pressure never dropped too low. However, I only did a short test drive, drove it home, then took it to the mechanic.

ETA - mine was an E reg!
 

Matafleur

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They did do a test drive, I picked it up about 10 mins after they had got back with it! Unfortunately because it was after hours I paid and they left. I filler up at the fuel station opposite the garage and the light was on when I started it again. It may have been on before but I only drive it 30 yards so didn't pay any attention.

Pressure comes up quickly on starting and holds pressure no problem. Plenty of brake fluid. They have put on a new brake fluid container which seems to have a different type of sensor but doubt that would be an issue.

I hate lorries. All I want to do is ride my horse!
 

Bob notacob

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The odd thing is that the handbrake also brings up the warning light. It is a full air system from a separate air tank. No hydraulics are involved. The service brakes are air over hydraulic and there are two separate systems.All three systems can bring on the warning light but usually it stays on. I cant remember is this vehicle has rear disc brakes .If it did and the pads were well worn ,then it could bring on the warning light as described however I would have fully expected a garage to have checked this.Failure of part or all of the hydraulic system results in the light going on and staying on. My conclusion is worn pads ,incorrectly fitted electrical contacts on the pads or an electrical problem.
 
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Matafleur

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Yes, agreed, comes on as soon as I apply either handbrake or brakes and goes off as soon as I release them. There are discs on the rear but the garage specifically said that these are fine as the fronts were badly corroded.

I'm hoping it's nothing serious after replacing most of the brake system and it having a thorough going over. I have only just bought it so they said they had highlighted everything they could find even if very minor. I have had everything fixed that they picked up so a bit gutted to still have a warning light on collection. I'm sure it would have come on during their test drive and they were happy with it then.

I think lorries may be worse than horses...
 

Bob notacob

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The brake pads have (unless someone has removed them)a platic lug clipped onto them with a wire going to it from the brake warning light system. If the pads are worn out,the lug touches the disc and makes electrical contact switching on the warning light.This will occur every time the brakes are applied ,either by handbrake or footbrake.
 
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