'94 f250 psd brake warning lamp

[nozel]

brake warning lamp illumnated park brake off with wire connected to park brame pedal assy.

Fluid level within specs

Question what other sources will cause lamp to be illuminated?

For t/s info: the DRL lights are always on with park brake set on (is this normal?)

thanks in advance
RZ

[bockhold]

is the parking brake completely off? some times it will stop at the first click and will trip the light.

whats drl?

[nozel]

Confrmed park brake fully off and
DRL = daytime running lamp factory installed on Canadian cars and trucks

[bockhold]

Description and Operation

Service Brakes
The brake warning light in the instrument cluster is used to warn of system malfunctions. The red warning light for the brakes can indicate three conditions:


The parking brake is not fully released.
The brake fluid level is low in the master cylinder reservoir.
The vacuum pressure is low on diesel engine vehicles.
Diesel vehicles use a low vacuum indicator switch. The low vacuum indicator switch is located on the left side of the engine compartment near the vacuum pump. The low vacuum indicator switch will turn on the brake warning lamp when a low vacuum situation occurs.

Rear Anti-Lock Brakes
The yellow anti-lock brake indicator lights up for approximately two seconds when the key is first moved to RUN or START for circuit proveout. The indicator also lights up when the RABS module detects a malfunction in the system.

The self-test feature contains codes that indicate the area of the malfunction. When a malfunction is detected, the RABS control module shuts down the system and the yellow anti-lock warning indicator comes on. This permits normal braking. A code can be retrieved by momentarily grounding the diagnostic pigtail (black with orange stripe wire) after it is disconnected from KAM (keep-alive power red wire) and counting the flashes of the yellow ABS lamp. To make sure the diagnostic trouble code (DTC) is not lost from memory, the key must be left in the RUN position before the diagnostic lead is disconnected from KAM power. If more than one diagnostic trouble code exists, only the first code stored will be displayed. Additional codes will be output only after the first fault is corrected.

[bockhold]

thats from a 97 service manual

it should be the same for a 94.

source is alldatadiy.com

[donald lorbeske]

is the pedle hard to push if so it might be your vac pump there known to go on those if vacuem drop out the light will come on iv replaced two on my trucks

[nozel]

"The parking brake is not fully released. "

Will not turn lamp on when park brake set (more t/s required)


"The brake fluid level is low in the master cylinder reservoir."

checked found at correct level

"The vacuum pressure is low on diesel engine vehicles."

found light went out after running engine and could get it on when pumping brakes multiple times. no further problem here

Thanks for the replies
RZ

[donald lorbeske]

if you pump the brake and light goes back on then you have a vac pump going bad if it goes on again just raplace the pump what your doing when running the engine is building vacuem my truck did the same thing you will have brakes but will be a hard peddle to stop there not that hard to replace the hard part is getting the pully of i used my vice and open it up spand the pully over the jaws and took a hammer and drift to the center came right off then use a bolt in the center to put it back on good luck take care

[toads250]

Vacumn pump I have replaced 4 on my truck the light on is a sure sign the pump is goin'

[nozel]

Originally Posted by nozel

For t/s info: the DRL lights are always on with park brake set on (is this normal?)

thanks in advance
RZ

brake system warning lamp is out with engine running AND
stays out when brakes pumped two or three times. BUT
warning lamp lights if brakes pumped more than five times...

lamp goes out witin 2 seconds of brake being released

Now t/sing why drl stays on when park brake set and engine running
This should cancel the drl and cause brake warning to illuminate.

Is the park brake switch a grounding switch?

Thanks again for your input
RZ