OJ Avery

IDK what the code was, it was cleared when I got to it this morning. I will look for the function parameters reset. Thanks MACKPRO, I'll let you know what I find

I have an odd one. 14 gu712 w/mp7. I'm the 3rd person to work on this so here's the story. Code for def quality. Derate for def quality on the lcd. Sensor was replaced, new def added. Same problem. Not sure what was done by 2nd person. I get it this  morning , no codes, derate for def quality on lcd. Cleared lcd warning with the guard dog. Drove for 20 minutes no problems. parked in my bay, off for about 10 minutes. Turn ignition on , lightning bolt and check engine light and def quality derate on lcd all on. after about 5 seconds lightning bolt goes off, a couple seconds later the check engine light goes off. Again I clear the derate message with the guard dog. No codes. I can't find a learned data reset or an acm reset anywhere in ptt. What is going on with this thing? Thanks

We've had a couple of the sensors go bad in Mack granite with mp7. We've also had drivers put washer fluid bin there too. blue cap?? blue (washer) fluid...duh. What a mess

Actually I did pull the connectors apart and pried the connector yesterday. Put it back together and turned on the mirror heat. Then I wiggled the harness at the back of the panel and I could not get it to go off. Thanks for the help turckster!!

ok, so I measured resistance , pin 4 to pin 27a... .5 ohm. Then pin 86 to 22b... 5.0 ohm. I wiggled the harness no changes. So then with everything connected , ignition on I pressed and held the switch and wiggled the connection at the dash panel and the light came on. So I have it positioned where it'll come on every time (so far ) but what would you recommend. I had my suspicions early on that the dash panel itself was bad. But I don't know what to do now. Should I order a dash unit? If I order a dash panel will it need to be programmed at the dealer?

Does ambient air temp sensor play a part in this ?

Also when I jumper pin 4 and 12 on the switch, press and hold button, I get 12 volts at the mirrors

turckster, I concluded that the instrument panel controls the ground circuit. But you cannot just ground that circuit, you'll pop the fuse. ZDB I felt I should have a lit switch with out the mirrors plugged in. Here is what I have.

At the switch I have power at terminal 2 with the ign on.

When you push the switch I have power at term 4 on the switch, and that power goes to term 27a on the instrument panel.

With ign off I have power at pins 85 and 30 at the mirror heater relay. With the relay plugged in I have power at pin 86 at the relay which sends power to pin 22b at the instrument panel.

I have continuity from pin 12 on the switch to the positive at the mirror. The Ground at the mirror is good.

ALSO.... I took the dash, the relay and the switch and installed them all separately in another 2013 gu and every time the heated mirrors worked.

I'm so lost on this

right mirror is new. I've checked for continuity and its good. Should the switch light with both them unplugged ? 1 Unplugged?

Its a fairly simple circuit, that's what's driving me insane. I swapped dash, relay and switch. All those components work good in another vehicle (13 GU)

The mirror motor works as it should. Checked powers and ground. not always understanding the circuit. The circuit goes thru the instrument cluster module. Wondering if that's the issue??

I have an odd one. I'm doing a mirror upgrade for our plow trucks that use a tow plow. Swapping the right stationary mirror for a motorized one. Both left and right mirrors heated of course. The heated mirrors won't operate. I unplugged both to see if the switch would light and it did....1 time. I pulled up the wiring diagram and everything I see is checking out. I have power to the switch at #2. When I press the switch #4 terminal lights like it should. I swapped the relay with another one with exact part number. The HTD mirror fuse at f15 is good. I replaced the switch just because I have one. Any help would be appreciated.

OTC makes a kit that works great for testing for air...OTC p/n 88800236...I use it often

So everything seemed to go well until last week. I heard from the residency mechanic that when its got a full load it shifts hard 1-2 and there's a code for a solenoid. Haven't seen the truck yet, will keep you updated. Thanks for all your efforts, I appreciate you all!!

I'm having troubles locating Allison service bulletins, specifically Allison sil 18-TR-98

Any help would be appreciated

Thanks BC Mack and Mack Pro. I contemplated sending the cooler out for pressure testing because even though I didn't know what the pressure at the cooler typically was, I knew I wouldn't be able to simulate it. But I went with a new cooler. Second try of course. I ordered everything before I took it apart, I ordered a 7 plate and this has a 17 plate cooler. Yes the cooler is below the output shaft. We've started servicing the Allison's here, and typically anything more than that we send to a Allison dealer, but I figured this wasn't a complicated process so we decided to keep the truck here. We have a couple hundred 13-15 Mack GU with the Allison and we've experienced very few problems.  Thanks again , I can always count on both of you to help out.

Hello??..is this thing on lol?? another question, I am having no luck finding any literature on this thing. I pulled the cooler and put it in the parts washer tank and put about 30# of air to it , no leaks. what is the typical pressure running through the cooler??

I have a 13 GU with a 3000/4000 series ( I think ) Allison in it.  Serial # 6610336363, cooling system is full of trans fluid so my assumption is the cooler is bad. its an internal one on the back of the trans. I'm not finding much literature on it so any help would be greatly appreciated. Is it as straight forward as the parts diagram shows? Do's and don'ts ?

Thanks!!

So you still do the harness and the updated oil pressure switches I assume.

Did I see on here that Mack says no longer replace ecm with an oil soaked harness? It has reached the ecm. Working on a 2009 mp7 w/ 07 emissions.

I am replacing an a/c compressor on a13 granite and I can not find anything in impact about r & r. How much oil goes in before install, ect

injector cups. if you do a cylinder balance test you'll see a couple injectors out of wack. I've had a few no code injector probs. It will clog the dpf quick or be doing regens (or at least trying) often.

I have a 13 GU with a mp7 and I had some unuasual codes. we also run a Verizon gps system off the diagnostic connector. codes..spn 251 fmi 12...spn 171 fmi 9...spn 2017 fmi 9...spn2029  fmi 9...spn228  fmi9...spn245  fmi9..spn251 fmi 9,2,13spn 3695 fmi9..spn 641fmi4 spn 84 fmi9 ..spn 91 fmi 9... what do you make of this? I feel they are all related to a common incident

ok thanks mackpro

I also have a pending code spn 3226 fmi13 after treatment nox cal value out of range... I cannot get nox sensor values in ptt, why? Ive looked at every test in ptt.