Catdaddy1958 Posted March 31, 2022 Share Posted March 31, 2022 Hi guys- new here. I drive a 2012 Pinnacle with M-drive, hauling mail. About a week ago it began failing to move, no throttle response, especially after hooking a trailer. Got it going a few times, but eventually had to tow it 3 hours home. It revs in neutral, but throttle response is disabled when R or D is selected. If you stab the throttle, it will raise the RPMs VERY slightly and fall back. Not enough to move the truck. NO fault codes on dash, gear indicator shows gear selection. I have ordered the cable to connect to my scanner- this is apparently the last year NOT equipped with a standard OBD2 jack- but I hope to get some insight here while I'm waiting. It started as intermittent, but is now completely inop. I did run my fingers over the harnesses that cross the frame. There was a similar post a while back, but no definitive fix or answer. TIA for all help- I'm retirement age, helping a friend get his new company off the ground. Quote Link to comment Share on other sites More sharing options...
Catdaddy1958 Posted April 7, 2022 Author Share Posted April 7, 2022 A little update- finally got someone to scan truck- who professes NO Mack experience. No help. No active ECU or VECU codes, but trans codes are: MID 130, PID 36- clutch wear status, and PSID 28- transmission brake. FMI 1. When this first started, it was intermittent, and the truck would eventually work and drove normally. (Weird, but MOVING the truck in neutral to clear the trailer made it work the first two times.) Is there an adjustment to correct this? Or a failing wear sensor? MACK won't work on it because of previous aftermarket repairs to the DEF system, and no one around PODUNK here seems to know anything about them. Quote Link to comment Share on other sites More sharing options...
Onyx610 Posted April 7, 2022 Share Posted April 7, 2022 I don’t know much about these besides the fact they are crap and that they are bound for failure. However here is a video I posted somewhere on here that might help you out a little. Unfortunately it sounds like it’s gonna need to come out and be rebuilt. I could be wrong and hope so. Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted April 7, 2022 Share Posted April 7, 2022 sounds like a clutch actuator problem, and I bet the truck is 'deleted' and thats why MackVo wont touch it... I am sorry, but you are screwed.. even if you replace the clutch actuator yourself, you still need to have the clutch calibrated, and the TCM will need updates, and a learn data reset.. NO DELETE'S !! sorry sir... Jojo 1 1 Quote Link to comment Share on other sites More sharing options...
Catdaddy1958 Posted April 7, 2022 Author Share Posted April 7, 2022 That was indeed a great video, and I have been studying this setup trying to figure out the issue. (Just FYI- I got my Advanced Engine Performance Tech rating in 1982- I have been doing electronic diagnostics for decades) INFO is scarce on Mack. What I have yet to ascertain is what the ECU uses to determine wear at either the clutch or transmission brake. It seems likely to me that the ECU disables the throttle because a sensor value is too high (FMI 1), but that doesn't necessarily indicate mechanical failure, When this happened the first time, I drove it another 3 hours OTR and swapped trailers before it happened again. I can't prove it, but the bump engaging the trailer seems to have moved something and caused it to reoccur... 1 Quote Link to comment Share on other sites More sharing options...
Onyx610 Posted April 7, 2022 Share Posted April 7, 2022 Like I said I can’t be of much help and don’t want to guide you in the wrong direction. I’ll see what other info I can find on these. Quote Link to comment Share on other sites More sharing options...
Catdaddy1958 Posted April 7, 2022 Author Share Posted April 7, 2022 6 minutes ago, Joey Mack said: sounds like a clutch actuator problem, and I bet the truck is 'deleted' and thats why MackVo wont touch it... I am sorry, but you are screwed.. even if you replace the clutch actuator yourself, you still need to have the clutch calibrated, and the TCM will need updates, and a learn data reset.. NO DELETE'S !! sorry sir... Jojo Do you know what data the ECU is seeing that makes it disable the throttle? If I stab the throttle, it raises the RPMs ever so slightly and you feel the clutch begin engagement. I do NOT believe this is a mechanical issue- unless it is the wear (reported by SOME sensor) has exceeded the limits- when it worked, it worked fine, shifting, pulling etc. Then it just disables the throttle, and reports FMI 1- data exceeds limits- but WHAT data? I'm considering an aftermarket or even dealer level scantool package to dig into this. It's just wrong to junk a truck because it has an issue that SHOULD be repairable. Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted April 7, 2022 Share Posted April 7, 2022 the clutch is operated by an air bag, the range of motion is measured by a sensor for the acuator .. to see it on the PTT screen t almost makes sence.. I have forgotten many of the fine points since ive been away from it for 4 years.. to me the bigger issue is the delete... these ECU's are very smart.. jojo Quote Link to comment Share on other sites More sharing options...
Catdaddy1958 Posted April 7, 2022 Author Share Posted April 7, 2022 Thought I ought to throw this out there- this transmission was replaced by the PO last year. Calibration was not done, vehicle has been in service one year since the tranny was replaced with a 2015 unit. Just found this out. This truck belongs to a friend I'm helping get a business off the ground. I own a Freightliner with a Detroit- much fewer issues with repairs and information... But I learned to drive a truck when there was more than ONE stick on the floor... Quote Link to comment Share on other sites More sharing options...
Catdaddy1958 Posted April 7, 2022 Author Share Posted April 7, 2022 (edited) 15 minutes ago, Joey Mack said: the clutch is operated by an air bag, the range of motion is measured by a sensor for the acuator .. to see it on the PTT screen t almost makes sence.. I have forgotten many of the fine points since ive been away from it for 4 years.. to me the bigger issue is the delete... these ECU's are very smart.. jojo I get that- but there are no active ECU codes. Is the travel adjustable, like the clutch actuator rods were on some older manuals? I bet that would restore the truck to service. I've seen a picture of the air cylinder- looks like an air operated version of the Mazda/Ford tranny mounted slave cylinder. Edited April 7, 2022 by Catdaddy1958 Quote Link to comment Share on other sites More sharing options...
Popular Post Joey Mack Posted April 7, 2022 Popular Post Share Posted April 7, 2022 it is unlike what you know in the older big trucks.. take the truck to someone that WILL plug into it and calibrate the clutch, cycle the shift forks in the tranny, and update the TCM.... that last one is probably Mack only.. You have a lot of knowledge about trucks, but unfortunately , like me and a bunch of others.... we cant do a damn thing if we are not a dealership with a $10,000.00 loaded computer that requires many updates to stay currrent... I run my own service truck and I use metal tools to make my living... I have a lot of knowledge about programming, but no interest at all in investing in it.. good luck sir,,,, jojo 2 1 Quote Link to comment Share on other sites More sharing options...
Glensts Posted April 8, 2022 Share Posted April 8, 2022 2016 rawhide. Similar symptoms as yours but when mine wouldn't shift you could hear an air leak as well from inside the bell housing. Thats where the shift valve is. Had to get trans removed, valve replaced and did clutch at the same time. Also got software upgrade for trans. Software upgrade was a lot nicer so we took our 2013 in for the update as well and it sure shifts nicer and at better times. Our lightning bolt would come on when it wouldn't shift and sometimes I had to restart it several times to get going. Once it was warmed up it was better but not perfect Quote Link to comment Share on other sites More sharing options...
fjh Posted April 8, 2022 Share Posted April 8, 2022 There is very little we can do to help here with out the codes or the computer program to read the truck take it to a dealer have it looked at! We can stab in the dark all day long here post the cheap and easy stuff however you need to take this magic stuff to the dealer for the most part! 1 Quote Link to comment Share on other sites More sharing options...
Onyx610 Posted April 8, 2022 Share Posted April 8, 2022 14 minutes ago, fjh said: There is very little we can do to help here with out the codes or the computer program to read the truck take it to a dealer have it looked at! We can stab in the dark all day long here post the cheap and easy stuff however you need to take this magic stuff to the dealer for the most part! He can’t because it’s deleted haha Quote Link to comment Share on other sites More sharing options...
fjh Posted April 8, 2022 Share Posted April 8, 2022 9 hours ago, Onyx610 said: He can’t because it’s deleted haha EVEN Worse! 😡 1 Quote Link to comment Share on other sites More sharing options...
Popular Post JoeH Posted April 9, 2022 Popular Post Share Posted April 9, 2022 (edited) On 4/7/2022 at 7:47 PM, Catdaddy1958 said: I get that- but there are no active ECU codes. Is the travel adjustable, like the clutch actuator rods were on some older manuals? I bet that would restore the truck to service. I've seen a picture of the air cylinder- looks like an air operated version of the Mazda/Ford tranny mounted slave cylinder. Any luck finding anything? I know you didn't specifically say you "deleted" the emissions, but that seemed to be the implication. Sadly Mack trucks don't respond well to being deleted, it brings on a whole plethora of problems. You might consider reinstalling the emissions crap (hopefully you didn't toss it....) So that you can use the dealer as a resource for diagnostics... I learned 15 years ago that once you venture away from Stock, you're pretty much on your own. Engines are engineered to work in a certain way, once you start changing variables it can get ugly fast. I suspect Mack (Volvo) engineers their programming to make their trucks go to shit if you try any funny business with the emissions. Edited April 9, 2022 by JoeH 2 1 Quote Link to comment Share on other sites More sharing options...
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