Dash Brake Light Flashing

Check your ABS, my brake light on the dash would come on at times when I applied the brakes, and what went out was the black box that controls the ABS. I have a 1993 K-1500, so if you have ABS I'd check that, the only thing is that black box ain't cheap so the mechanic just unhooked and heck the brakes work fine. The mechanic told me that it was only front ABS anyways so I really didn't need to replace that box. The only thing is that mine did not blink in a pattern, good luck with it and hopefully that info may help.

yep find somebody that has a code reader and have them hook it up and find out exactly what the problem is.

Get a hanyes book for your truck there is a list for all the codes your obd1 you ever show, and it explains what it is. It is also good to have if you dont have a great knowledge on your ride. I use mine everytime something crazy goes on, and I got a 92 350

hey, I have the same exact problem, and i cant find the solution anywhere. did you figure it out?

you have a fault with the abs system. very simple system on these as they only have rear wheel abs. either the wheel speed sensor is bad in the rear, or the abs module is bad.

Hi, I have a 1990 K2500 4x4 chevy chyenne 350 V8 700r4 7200 gvw 280000miles on the clock! My dad just bought, and I am helping him fix it! The brake light was on and I think I have it figured out. Here is how to fix it; -first with the truck off and in park on a leval ground release the ebrake and turn the key to run does the light com on for two seconds then remail light? Start the truck up is the light still on? If not then the ebrake switch may be bad. -second wiht the key off install a 16 gauge jumper wire between pins A & H on the ALDL OBD 1 connector below the drivers kick panel, then trun the key to run, wait 20 seconds the lamp should flash ounce then blink quickly, count the blinks this corrosponds to the trouble code. example one long blink three short blinks means code 13 The ssytem will repeat each set code three times then move on to the next one, if there are no other codes it will repaet the set code over and over agin untill you tunr the key off and remove the jumper. -To reset codes remove the brake hazzard fuse for 5 seconds then reinstall. I will folow up with a list of trouble codes.

edit aldl connecter is just under the knee bolster, and you don't need to remove anything to see it or get at it. I got code 13 on my truck codes 13,14,15 are a failed module code. the module is mounted to the bracket on the brake master cylender under the hood..black box I went through two modules before I found out that if the soliniod dump valve is faulty it will instantly blow the module and set another code 13. Here is how to check the soliniode dump valve. The dump valve is the alluminum block with two soliniods on it mounted below the brack module and has a 4 pin connecter going into the brake module, and two brake lines. Remove the grey or black 4 pin connector and check the ohms across pins D to A 3-6 ohms and pins D to B 1-3 ohms measured from the harness end. If these are not within these values it will fry your new modual. grey or black 4 pin connector D black C Blue B white AOrnage I replaced the soliniod dump valve and modual from the wrecking yard, I plugged them all in wihtout installing or removing any brake lines. make sure you disconect the battery when disconecting and reconnecting components. After this my brake light went out, I will permanately install these parts in a couple of days and folow up on how it went. local wrecking yard prices bc canada; soliniod dump vavle 20-50 dollars New GM price $334.00 Rock Auto price $ 119.00 module 20-30 dollars New GM price $225.00 Rock Auto price $ 69.99 refrences; -Auto Zone free repair info and wrring diagrams plus trouble code charts - Rock auto interchange info & prices Hope this helps maybe a litlle different from year to year but this should work on any 88-94 GM or Chevy pickup. Let me know if you have any questions this repair cost me total of $58.00 including paying my slef a dollar an hour for 10 hours! lol!

Code 2: open isolation solenoid or EBCM malfunction Code 3: open dump solenoid or EBCM malfunction Code 4: grounded anti-lock pressure valve rest switch Code 5: excessive dump valve actuations during anti-lock stop Code 6: erratic speed signal Code 7: shorted isolation solenoid or EBCM malfunction Code 8: shorted dump solenoid or EBCM malfunction Code 9: open or grounded speed signal circuit Code 10: stop lamp switch circuit Codes 1, 11 and 12: invalid diagnostic trouble codes Codes 13, 14 and 15: electric brake control module malfunction PRELIMINARY DIAGNOSIS Before reading trouble codes, perform the Diagnostic Circuit Check according to the chart. This test will aid in separating RWAL system problems from common problems in the hydraulic brake system. The diagnostic circuit check will direct the reading of trouble codes as necessary. READING CODES The RWAL ECU will assign a code to the first fault found in the system. If there is more than 1 fault, only the first recognized code will the stored and transmitted. Trouble codes may be read either though the use of TECH-1 or equivalent scan tool or by connecting a jumper wire from pin H on the ALDL to pin A. If the jumper method is used, the fault code will be displayed through the flashing of the BRAKE warning lamp on the dash. The terminals must be connected for about 20 seconds before the display begins. The display will begin with 1 long flash followed by shorter ones-count the long flash as part of the display. Sometimes the first display sequence will be inaccurate or short; subsequent displays will be accurate. If using a hand scanner, note that if a soft code is stored, only the last recognized code will be retained and displayed on the scanner. Soft fault codes 6, 9 and 10 can only be read with a scan tool. Codes 1, 11 and 12 will not read on the scan tool; they must be read using the jumper wire method. Never ground terminal H of the ALDL to terminal A if the BRAKE warning lamp is not lit. Doing so will set a false code 9 and illuminate the BRAKE warning lamp. With the brake lamp on, the RWAL system will be disabled. CLEARING CODES Stored trouble codes must be cleared with the ignition switch OFF . Remove the STOP/HAZARD fuse for at least 5 seconds, the reinstall the fuse.

"have a 1992 Chevrolet C/K 1500. My brake light on my dash has been on ever since I got it, and today the light started blinking in a pattern. I've looked everywhere, but I can't find anything about it. The pattern is 3 short blinks and 1 long blink. Any Ideas?" mine did that when I tried the blown module wiht the isolation dump vlave completly removed. you are getting code 13 blown module, and most likely a failed isolation dump soliniod. Check rock auto for interchange the astros S10 etc.. used the same module, the isolation valve will have to be from a fullsize pickup and same GVW rating, and same year range. isolation dump valve

abs computer and diagram explaining isolation dump valve test procedure

Update installed the parts today, light went out and stayed off yeah!! However the brakes still pulsate, seems the drums or rotors are warpped? Don't know which? Useually the steering wheel shakes back and forth when the rortors are warped and this truck dosen't do that, so I am not sure. It has new pads and rotors front flex lines, and folowing the dump isolation valve new fluid and full bleed.

replaced the front rotors, brakes work great!!!!!!!!!!!!!!! Question about RAWL brakes do you pump them or not? I know you should not pump 4wal aba brakes

88-94 Chevy trucks ralw brakes suck, I read a post of how many folks have spongy brakes and indicator light problems. Abs brake system desigh is bad when working or not. Many found the best solution is to unhook abs from control box wiring and remove the dump valve and pipe direct to perporsion valve for good results. Check out www.gmt400.com/threads/1990-c1500-abs-rwal- removal.11427/ good pictures,advice and instructions

GM ABS bad right through to early 2000's, actually. They were too sensitive and activating unnecessarily which can actually cause an accident. When i get an older gm with an ABS block that still works, i remove the ABS fuse to disable the system. Bf's 2000 jimmy stops way better since doing that, and my 96 K1500 would stop on a dime even in snow without ABS. I have an 89 c1500 now, brake light was on steady then the other day switched to a pattern of 4 short flashes followed by one long; until finding this thread, i had no idea it had ABS! Anyhow, glad to know it means the ABS isn't working; as soon as the weather gets better, i'll remove/bypass it. In the meantime, i think a piece of electrical tape ought to solve the blinking light problem, lol!

Hey Ben, don't know if you solved your brake problem yet? I saw the post, and I have the exact problem. My guess I'd you have what is called a dump valve under you master cyl which means you have rear only abs. Your code is not 13 it is 4. Speed sensor. Mine flashes because my speedometer has bad connection. Anyway you don't want to ignore it because your back brakes are not working, or not enough anyway. Like with mine when the speedometer stops the abs brain senses no movement therefor sends no fluid to the back. Hope this helps

I have an '88 2500 Cheyenne. The brake light in the dash blinks 8 short then one longer flash. Can someone please help me figure out what this means? Which code is this and how do I fix it?

If you have an 88 then you have rear only abs and the thread before you hit the nail on the head. You count the number of flashes short or long, and that is your code unlike the check engine light where you count them separately. You have a speed sensor that is basicaly part of your output shaft so if you changed transmission and put a different year in it you have big problems. Because like the thread before mentioned if speed sensor doesn't work the abs brain registers no movement and sends no fluid to rear brakes, also your speedometer is electronic meaning no cable and if it's not working no rear brakes. I spent about a year trying to figure all this out. Not much info out there. From what I gathered the best thing to do is eliminate it U Tube will show you how

Disconnect both plugs from the Rear Wheel Anti Lock module located beside the brake booster. Clean contacts. Plug it back in. If it is a dirty contact, that will solve the problem. Sometimes when the battery is disconnected briefly, the module does not "learn" correctly.

My 2001Tahoe's ABS and brake light have been on for 15 years. Yesterday the brake light started flashing and the annoying alarm stay on as long as I was driving, stopped when I can to a stop also did not do it in reverse. I depressed my E brake then released the alarm went off and brake light stopped flashing.