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MaxBrake Does Not Like Sensor?

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275hp cummins enough?

Better ride

Well, I spent some time trying to install my new MaxBrake. Came across a couple of things I wanted to share. I will apologize in advance for a long post, but I need to vent.



1. - The control unit is huge! At least compared to my Tekonsha Prodigy. Now I know the Prodigy is not the best brake controller on the market but it sure did mount nice. I have everything torn apart to allow mounting the new control head which has required other items to be removed or miniturized. Again, not the end of the world but worth mentioning for others who have yet to do the install. Its size does limit options, especially if there's other "stuff" already mounted in your cab.



2. - The power/brake pedal harness is identical, at least for my application. I verified the pinout and was able to plug the harness from the Prodigy directly into the Maxbrake. Please double check yours, lest you let some smoke out of something expensive!



3. - Putting the "tee" in the brake line was real easy. I used the 8" line supplied in the kit to mount the sensor for now. Since my branch on the "Tee" is pointing straight down, I plan on shortening that up a bit later on. I just don't have access to large fitting supply places right now.



4. - The sensor cable. The cable included in the kit has two different ends, an "A" and a "B" that will both plug into the sensor. The instructions clearly state that "B" is only to be used for factory testing. OK, fine, but why create a situation where someone may plug in the wrong one? If its for factory testing only, why do I need it? What happens when that other end gets covered in mud or water in my engine bay? Will the exposed pins short and do any damage to the control unit?



And now for the bit that prompted the name of this thread. Once I knew the power harness was compatable, I plugged it in. Unit lit up and after a few seconds gave me a couple of warnings, something about checking the sensor and checking the trailer wiring. Both are reasonable considering the sensor cable was not run at the time and I do not have a trailer plugged in. So far so good. I unplugged the unit and put it aside while I ran the sensor cable. Problem is when I plug in the sensor cable. Based on #4 above, I triple checked and verified that I had the "A" end plugged into the sensor. Then I plugged the 8-pin jack into the control unit, and finally, the power harness. Flipped the unit over and ... ... ... . nothing. :confused:



The screen is blank, no backlight, nothing. As soon as I unplug the sensor cable it seems to fire right up. If I plug in the sensor cable now, the screen goes blank again. Pull sensor cable out and it goes through the startup routine from the start. Disconnected the actual sensor, same result. Ignition on or off, same result. Leads me to believe I have a bad cable. We'll see what the MaxBrake people have to say in the morning.
 
Hmm, I installed mine yesterday with no problems. I did use the Maxx Brake harness. I followed set up instructions and everything is a go.
 
I installed mine about 1 ½ years ago, everything went without any problems.



The only thing that I did different was to have a local hydraulic hose company make up (with proper end fittings) a short piece of flexible hydraulic brake hose and then attached the pressure transducer to it and eliminated the 8in. steel tube. I didn’t like the relative heavy pressure transducer vibrating at the end of the 8in. steel tube.



I agree though, in the age of miniaturization the head is overly large and cumbersome and the mounting bracket leaves something to be desired. It is STILL the BEST brake controller on the market!



Richard
 
I talked to tech support at MaxBrake today. The gentleman that answered the phone was very helpful. It appears my sensor cable has an internal short and the control unit powers down to avoid damage to the unit itself. A replacement cable was offered, but to be honest, with the truck in pieces it'll be quicker for me to cut the end off the exisiting cable and make a new one. Plus, it will solve my issue of having the "factory testing only" end as I'll not include it in my rebuild.
 
I'm glad to hear you have determined the cause of the problem you had. You'll love the MaxBrake once its hooked up and towing.
 
Upon tear down, the short was found about one inch from the end that plugs into sensor. Looks like it got a little too warm while the heat shrink tubing was being shrunk and the two wires got a little cozy.



Upside is that the cable is back in the truck and one of my complaints from the original post (factory test pigtail) has been dealt with, as I only wired in the "A" pigtail. The "B" pigtail is now a spare for possible future use. I'll be able to do a final test before putting the dash back together in the daylight.



Only downside right now is that I won't be towing again until mid July so I won't be able to comment on the improved braking action till this summer. :{
 
Need help I have the max brake and loved it . I sent my avalanche in for repairs and now its not working display is on but when I plug camper wire onto truck controller read self test failed. I tried to reset and no good would it be pressure sensor.
 
never figured out what maxbrake did to fix the self test failed. we can try a two-stage hard reset just to see if that would work if you'd like to call me at 941 416 0918 10 to 10 p.m. 7 days a week central time right now hugs Di
 
Dutch/Di
My Maxbrake is about two years old and the display is growing dimmer and I can no longer see it (except at night),
Have you ever seen this? Perhaps it is changeable from the menu but I no longer have the instructions.
Rog
 
Hi. I've only had 2 customers in 5 years who had an issue with dimming. The 1st one was sent back to MB and he put in a 2nd "eye" by the 2st one and returned it to the customer who let me know it was bright enough now. I do not know how MB did this and never thought to question it at the time.
I had a customer from Australia who had a dim display light. I contacted MB and they had me pass this info on to my customer.
For maximum brightness (and no dimming), it is possible to solder a 100 Ohm 1/8 Watt resistor in the empty holes next to the photo eye.
The backlight will still turn off after 5 minutes of inactivity, but will always be at maximum brightness when in use.
This can be done by an electronics hobbyist instead to international shipping to get it back to me then ship it back to you in Australia.

Please let me know if this is something you can do or maybe find a hobbyist to do for you. If it doesn't work, I can try searching back through old paperwork to see if I can find something else for you. I am trying my best to help any MB customers that I can.
There is nothing in the manual that will address this but if you e-mail me your name and address at -- email address removed --, I will send you a new manual so you'll have one. I do have a few left. Hugs,Di




Dutch/Di
My Maxbrake is about two years old and the display is growing dimmer and I can no longer see it (except at night),
Have you ever seen this? Perhaps it is changeable from the menu but I no longer have the instructions.
Rog
 
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Di,
Thanks so much.
I did not remember the manual mentioning the display either so we won't bother with the manual.
Now that I know what to look for, I'll drag out my electronic skills and I am sure I can fix it myself.
Hug's back,
Rog
 
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