abs braking system

I have read alot about the abs braking system used on the 91 cherokee. My pump sounds like its running on and off at a scheduled interval for long periods of time(probably about to burn out). I was wondering what causes this to go bad and maybe catch it if it was a sensor or pressure releif valve? Any help is appreciated i checked all fuses reset system and the pump still sounds on her last leg. Runs strong at start up building up desired pressure but once driven starts cutting in and out. Thanks again!

jason

It could be a pressure relief valve causing the problem or maybe a pressure switch hard to diagnost with out a scan tool. I think the 91 uses the Bendix 9 Abs system and has to have a scan tool for codes and tests.The pump should run for 60 to 80 seconds when the key is first turned on, any longer indicates a problem with the system.

check with your dealer, a lot of your system, including the pump has a life time warranty.

i changed the whole system on my 89 to the standard booster from an 88. You will know when your pump stops working because you will have no brakes and maybe kill yourself or somebody else. I wasn't willing to take that chance, free or not.

I have read alot about the abs braking system used on the 91 cherokee. My pump sounds like its running on and off at a scheduled interval for long periods of time(probably about to burn out). I was wondering what causes this to go bad and maybe catch it if it was a sensor or pressure releif valve? Any help is appreciated i checked all fuses reset system and the pump still sounds on her last leg. Runs strong at start up building up desired pressure but once driven starts cutting in and out. Thanks again!

jason

I just checked on the web about your system....
search bendix 9 abs jeep....
Major and serious issues.....dealer repair or conversion recommended.