Brake light DASH
Thread Starter
8th Gear
Joined: Dec 2011
Posts: 8
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Brake light DASH
Thanks for all the input on replacing my master cylinder, bleeding went fine, installed new master cylinder no problems, BUT, before the brake light would come on when trying to stop until the brakes were pumped up. Now brakes work fine, no pumping, BUT the brake light on dash stays on from start until I turn car off, any ideas?
regards
regards
Safety Car
Joined: Aug 2009
Posts: 3,752
Likes: 276
From: Melbourne, Victoria, Australia
Remove the brake warning switch on your master cylinder and refit it.
If the brake pressure between the front and rear is off (unequal pressure front to rear) the warning light will illuminate. Some master cylinders bias pistons have a recess and will lock the brake warning switch plunger.
If it still shows the brake warning there is air in the lines and the front to rear bias is off. (most people bleed the master cylinder before fitting it) then bleed all the calipers. Note there is a stop screw in the master cylinder (left side) that needs to be fitted with with the pistons fully in out of the car or it will restrict the piston movement that should be done when it was assembled.
If you get get plenty of brake fluid out of all calipers that will be fine.
If there is hardly any out the back brakes then check that
You can test this by putting your vette on stands and get some one to apply brake pedal pressure when you spin the wheel to see if they all stop the wheel, remove your ABS fuse to test.
You can also brake sharply with the abs fuse removed (make sure you have no one behind) and see if the front or rear brakes lock, you never want the back locking first but see if all 4 wheels do.
Hope it helps you
If the brake pressure between the front and rear is off (unequal pressure front to rear) the warning light will illuminate. Some master cylinders bias pistons have a recess and will lock the brake warning switch plunger.
If it still shows the brake warning there is air in the lines and the front to rear bias is off. (most people bleed the master cylinder before fitting it) then bleed all the calipers. Note there is a stop screw in the master cylinder (left side) that needs to be fitted with with the pistons fully in out of the car or it will restrict the piston movement that should be done when it was assembled.
If you get get plenty of brake fluid out of all calipers that will be fine.
If there is hardly any out the back brakes then check that
You can test this by putting your vette on stands and get some one to apply brake pedal pressure when you spin the wheel to see if they all stop the wheel, remove your ABS fuse to test.
You can also brake sharply with the abs fuse removed (make sure you have no one behind) and see if the front or rear brakes lock, you never want the back locking first but see if all 4 wheels do.
Hope it helps you
Last edited by gerardvg; Dec 30, 2011 at 08:51 PM.
