Electric brake lock switch maintenance?

[zebedee]

Ok - been through TM's and searched forum (question was asked once but no replys), I can't find maintenance / testing for the EBLS for M816 - looked through electrical and brakes also special equipment (wrecker)...

Can some one please point me in the right direction - TM or personal experience. Thanks..

Yet another "nuisance" pic incase you need visuals!

 

[73m819]

With truck running(air pressure up), step on brakes. push brake lock button, release the brake pedle, put truck in gear, if it acts like the brakes are locked up, the brake lock is working.


To release, press brake pedal down once(with air pressure up). That should release it

 

[SCSG-G4]

You need to look in the -20 manual. In short, unhook the switch, then use a VOM to measure resistance across the switch in both positions. Should be infinity when not depressed, and very low when pressed. Use the term "Microbrake" to find it. the actual manufacturer is MICO.

Also, be warned that if you really slam on the brakes, then set the switch, it may be difficult to release the rear brakes without bleeding them. Got to have more pressure on the front side than the back side to get them to release. The physical hydraulic switch in the brake line is difficult to get to and cost Uncle Sam several hundred dollars (BTW, it has a 75 day lead time to make, if you need to buy one).

 

[zebedee]

Thanks Ron, I am fine on the operation - which I tried but it doesn't do anything.. Though I thought it was press switch then depress foot pedal...

You need to look in the -20 manual. In short, unhook the switch, then use a VOM to measure resistance across the switch in both positions. Should be infinity when not depressed, and very low when pressed. Use the term "Microbrake" to find it. the actual manufacturer is MICO.

I guess I hadn't looked hard enough! '20 .. Which section - Electrics (didn't see) or brakes?

Also, be warned that if you really slam on the brakes, then set the switch, it may be difficult to release the rear brakes without bleeding them. Got to have more pressure on the front side than the back side to get them to release. The physical hydraulic switch in the brake line is difficult to get to and cost Uncle Sam several hundred dollars (BTW, it has a 75 day lead time to make, if you need to buy one).

Thanks a million for that tip - when I get it working, I don't want to screw it up!

 

[73m819]

star electric (keven ) has the hyd. block valve