Brake light indicator on

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Sep 13, 2011 | 07:48 PM

lonesomeloser

Thread Starter

Member

Joined: Dec 2008

Posts: 379

Likes: 2

From: Middletown, MD

Car: 1983 Z28

Engine: 305

Transmission: 700R4

Brake light indicator on

Ever since my engine swap, the idiot light for the brakes is on. I also upgraded to a newer style prop valve along with the 4th gen rear. Any ideas?

Sep 13, 2011 | 08:07 PM

eseibel67

Supreme Member

Joined: Jul 2009

Posts: 2,328

Likes: 10

From: Kitchener, ON

Car: 1988 GTA

Engine: LB9

Transmission: T5

Axle/Gears: 3.45

Re: Brake light indicator on

Only 2 possibilities. Either air in the system or the park brake switch is tripped.

Since you changed some parts, my bet is air in the hydraulics. Bleed them again.

Sep 14, 2011 | 06:16 AM

JamesC

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iTrader: (5)

Joined: Aug 1999

Posts: 19,282

Likes: 103

From: Lawrence, KS

Car: Met. Silver 85 IROC/Sold

Engine: 350 HO Deluxe (350ci/330hp)

Transmission: T-5 (Non-WC)

Axle/Gears: Limited Slip 3.23's

Re: Brake light indicator on

From the manual:

"The pressure differential warning switch is designed to constantly compare front and rear brake pressure from the master cylinder and energize the warning light on the dash in the event of a front or rear system failure. The valve and switch are so designed that the switch will latch in the "warning" position once a failure has occurred. The only way the light can be turned off is to repair the failure and apply a pedal force to develop approximately 450 psi line pressure."

I assume the wiring is attached to the combination valve.

JamesC