Parking brake warning light on after bleeding brakes

[aziff]

While flushing my brake fluid today, I noticed the parking brake warning light [the (!) (P) light, not the ABS light] came on after I finished with the first caliper. I started at the passenger side rear and did the 2 person pump and hold process. The tubing that was connected to the bleeder was pretty snug and I didn't let the master cylinder get anywhere near empty during the process. I also made sure that the person pumping the brake pedal for me wasn't letting it back up until the bleeder was closed each time, so I don't think any air got sucked back in.

Now that the light is on, I have 2 thoughts - the light may be on because 75% of the system is still full of old dirty fluid (I still have 3 wheels to bleed), or I messed something up and I don't want to do any more damage until I can take it to a shop and have it looked at. The caliper that I did finish went well; my fluid went from dark black to about the color and clarity of gasoline after bleeding about 300ml of fluid out.

I went for a spin around the block to make sure everything was still working and to find out how the pedal felt, and it was still nice and tight.
A friend suggested that the warning light may just need to be reset with a scan. Before I book it in to a shop and pay for them to tell me the problem, can anyone give me their input on the problem?

[brcidd]

Unplug the brake fluid reservoir float connector- does light go out? If so this is the source of your issue,

Also, are you sure your helper did not partially engage the parking brake? and light is on from that switch?

[aziff]

Originally Posted by brcidd

Unplug the brake fluid reservoir float connector- does light go out?

where might that be

[aziff]

scratch that. I went out and unplugged the electrical connection on the side of the master cylinder and ta da, the light went out when i started the car. I shut it down, plugged it back in and restarted and it was on again.

Question is, what does it mean and how do I fix it!

[brcidd]

Typically it means you are low on brake fluid- and I assume yours is nearly full- if not, definitely fill it up... so.... I'd tap on it, wiggle it, poke at it-- and even add more fluid until it starts working properly. Or you can leave it unplugged for awhile and test it once a week, until it decides to work. I'm not sure if it is serviceable, by itself.

[aziff]

is it possible that the problem could be related to getting air stuck in the line after bleeding it, even tho i`ve tracked the problem down to the sensor, or is it a pretty sure bet that it is the float sensor

[brcidd]

Most definitely the sensor-- is it covered up by fluid? If not it should be...

[aziff]

oh ya, it`s covered... the fluid is up to the max line. I was thinking about suctioning a bit out to see if i can catch a peak at the sensor and get it to float back up...