Hi all,

Last week the BRAKE warning light on my 2003 S40 started coming on whenever I turn to the right. Even going around a subtle right hand curve causes it. I checked the fluid level and its up to the max. Also no issues with the brakes that I can tell. My rotors are a bit worn but the pads are good.

My manual says this about the light:

Brake Circuit not working (brake fluid level too low) and EBD

When it says Brake Circuit, does that mean the electrical connections too? If I have a brake light out will that cause the BRAKE warning light to come on? I checked the lights and they work, but if there is water trapped somewhere and ona right turn the water shorts out one of the lights... maybe thats it?

Any other ideas?

Thanks,

 

I think it's just the level sensor inside the brake fluid reservoir. If the fluid gets too low the light comes on. It could also be just a malfunctioning level sensor. On my 2005 the connection to the sensor was loose and the brake warning light would come on randomly. I finally found the problem when I pressed the electrical connector a little bit harder than previously and heard the satisfying "click" as the connector was properly seated.

A brake light out would set off the bulb malfunction light which is a different warning light.

 

I know it's an old post but I need to know how it was fixed since I have the same symptoms on my 2001 S40. (Note: Not a fluid level issue)

 

did you try replacing the reservoir cap/level sensor?

 

That mean to replace the whole reservoir?

 

Google Volvo part number 3345685 - the fluid "decanter" goes for about $35 online. Sorry my S40 is at college right now so I can't look at mine but I believe you are correct in that the cap is plain and the fluid level float/sensor is part of the container. On my 850 the sensor is built into the cap.

 

Thank you for your help. I understand it's "just" a bad reading issue from the sensor and doesn't affect the braking system (then safety). I will look for a replacement shortly anyway.

 

Hi, OP here,


Unfortunately my S40's timing belt slipped shortly after posting this and I scrapped the whole car. So I was never able to even try to fix this issue. However, if memory servers me right, I believe others are correct in that problem was the sensor in the reservoir. Good luck!


A little tip... if you ever try to replace the timing belt yourself use the Volvo kit. A bad bearing in one of the timing belt idler pulley's went out causing the timing belt to slip. Head/valves were trashed, not worth the $ to try and fix.

 

I would make sure everything is dry and you don't have any leaks in the wheel wells. I had a leak on the right side and it wouldn't trip the light until a hard turn.