2004 Jeep Grand Cherokee brake pedal low

[jeep5820]

I have a 2004 jeep grand Cherokee. Had rear brakes done rotors & pads. Front brakes are good system was bleed out thoroughly. The brake pedal is low the abs light is on has been for many years. Any idea as to why the pedal is low?

 

[wlk]

Were all calipers bleed out properly or just fronts? Sounds line air or something w master cylinder, maybe air in there, idk. Couple ideas where to start, also make sure there are no vacuum leaks

 

[97prizm]

Could be the master cylinder or a vacuum issue.

 

[jeep5820]

All lines were bleed out, could it be the ABS unit or the Master Cylinder?

 

[jeep5820]

How to tell if Master Cylinder is bad?

 

[PontiacHO]

Pump the park brake 10 times.

 

[jeep5820]

You mean pump brakes in park ? Engine running?

 

[CleanSump]

Did you use a scan tool to do the ABS Module bleed? Some people have been known to drive on gravel parking lots and lock the brakes up a few times and then rebleed at the wheels. You'll feel a good shudder when the ABS activates. Not that I ever did such a hillbilly procedure

 

[jeep5820]

No I had mechanic do the job. He replaced some brake lines and did the rear brakes. He said he got all the air out. The pedal still low. Was not sure if the cause is the abs being the light is on? He said the wheel sensors are bad.

 

[BC1]

That ABS light does not effect the brakes working or the pedal height. That light has to do with ABS not working during panic braking or on some ice not normal braking.

Was the pedal low before you took it to the mechanic? If this happened after then take it back and have them fix it. Most likely there is still air in the system somewhere.

 

[BC1]

You need the ABS codes or live data before firing speed sensors at it. $2 says you have bad/cracked solder joints on the main power and grounds on the module board. Hacksaw, solder and some RTV have repaired the last 3 WJs I have owned.

 

[jeep5820]

Yes pedal was low before taking it to him., Maybe master cylinder jeep has 200k on it .

 

[D60]

Yes pedal was low before taking it to him., Maybe master cylinder jeep has 200k on it .

I've had really questionable luck with aftermarket MCs. If you opt to replace, don't go cheap. I have no idea if OEM stuff is still available for a WJ?

I'd first pressure bleed and reverse bleed before condemning the master.

Pull codes but wheel speed sensors (WSS) won't cause a low pedal

 

[meep]

Low pedal is either air somewhere in the system, potentially mis-fit brake pad (tangling with shim?) or improper pushrod adjustment to the MC.