Have a 2006 D8r ii 6yz1361. Back story we’ve recently replaced all injectors and injector harness inside valve cover l. Last week started throwing code for bad injector#3 it was in 26 minute intervals. Das done some diggin found where harness had been patched up that came out of valve cover so we replaced it anyway since it was patched up. Didn’t fix our issue. Today we had cat come out and they brought Ecm to flash it. He insisted that he had to eliminate all other options before replacing Ecm. Long story short he wanted to swap #3 and #4 injector to see if the code followed it. Well no it didn’t no we’ve lost the transmission!!! All pressures checked out so it’s not mechanical. Any thoughts? He was ohming out speed sensors when I left.
my guess is power train ecm is not seeing engine speed output from engine ecm if you suspect engine ecm is going out, cats stance on ecm's is that they are rarely the problem
Agreed on the ECM. Usually they are the last in the dagnostic line to suspect having failed. They do fail from time to time though, so not totally unknown. Has the tech tried re-flashing the engine ECM with the appropriate software for the engine S/No.? In the past I've seen that fix all sorts of weird engine ECM issues. What Diagnostic Codes were showing other than the one for the injector.?
Machine has 27k hrs on it. The codes I couldn’t tell you off hand. But we’d lose throttle button. For instance be clicking right along full rpm and boom fall down to 900rpm or less.
For symptoms such as you are describing getting a list of the Active Codes is the only acceptable first step to diagnosis. Note ACTIVE Codes, not all of them. There may be Codes on the list that were there once but are not there now, known as Logged Codes. Simply scroll through the Codes on the CMS panel and note down every Code where the SERV CODE icon on the RH side of the Monitor Panel window is lit up.
Headed to machine now. And another fun fact the technicians computer was broke so he was using our ET yesterday. Thought that was kinda funny.
Ask for a discount off the bill............
I plan on that. For sure. This guy is convinced it’s mechanical. I’ll get you the codes when I get back and part number of the main harness we changed already.
When this is all sorted it might pay you to take a look at the Click Box thread if you haven't already and read up on how to erase Logged Diagnostic Codes. You don't have to buy or build a Click Box. There are some posts on Page 3 of the thread showing how to do it with nothing more than 2 short pieces of automotive wire. HeavyEquipmentForums
We have click box and ET. I havnt read the thread being how we havnt had sever issues like this.
Even better. You can get the CMS Panel into Diagnostic Mode (Mode 3) with the Click Box and erase all the Logged Codes just leaving you with the Active ones. TBH I'd try doing that first. That way you won't be overwhelmed with a long list of Codes.
113 671.02 673.02 691.05 692.05 693.05 694.05 695.05 697.05 Active 113 1488.06 Harnes we changed 145-3850
So you changed the main engine harness 145-3850 and also the 122-1486 injector wiring harness.? All of those Codes above are powertrain ECM. Nothing on engine, that would start 036. Do I understand you correctly that out of that list above 1488-06 is the only Active one.?
Yes and yes to both questions.
The implement detent code
To list all the others.......... at some point there was a major electrical/electronic hiccup in the transmission. The current below normal is usually an open circuit somewhere. The signal issues probably the same thing, but intermittent. 671.02 - Trans Output Sensor #1 - signal erratic, intermittent, or incorrect. 673.02 - Trans Output Sensor #2 - signal erratic, intermittent, or incorrect. 691.05 - Reverse Clutch solenoid - current below normal. 692.05 - Forward Clutch solenoid - current below normal. 693.05 - 3rd Speed solenoid - current below normal. 694.05 - 2nd Speed solenoid - current below normal. 695.05 - 1st Speed solenoid - current below normal. 697.05 - Priority valve solenoid - current below normal. Interestingly there is nothing related to a failure of communication between the engine ECM and the powertrain ECM. Based on that I tend to agree with the tech that it is likely something mechanical.
Do you think it could be tcm? Or harness to tcm? And what about the injector code yesterday?
Yesterday we’d push scrapers and run it and it would go for 26 mins then drop back down to idle then let it set for awhile then it would work again and he did a stall test and that’s when the trans issue appeared…
The weird thing is that the injector Code is not even on the list. Not saying it wasn't there yesterday but there is no evidence of it now. It should be still there but logged provided no-one went in with ET or the Click Box and erased it. If the problem was erratic communication between the engine & PT ECMs then there ought to be something logged in both ECMs for CID 0246 FMI02, Cat Datalink signal erratic, intermittent, or incorrect.
Somethings rotten in Denmark
I gotcha. What voltage should we have at shift silinoids. (Spell check) on second gear forward and reverse it has 5.5-5.7
We have correct pressure at relief valve. Tech is thinking it’s the modulating valve. Oh yeah we’re doing the site work for the new Cat store to lol! Got cat dozer broke down on cat property with cat mechanic I told tech sounds like it’s all cats fault lol.
Seems like the injector swapping and the tranny fail are related. Have all the wire harness connectors been checked for tightness and corrosion?
How are you checking voltage.? Back-probing with the solenoids still connected electrically to the machine, or sticking the DMM probes in the harness connector with the solenoids disconnected.?
Update on the transmission solenoids. They are activated by 24v but using a PWM signal to modulate the operation of the solenoid valves, so a DMM will not measure 24v at an energized solenoid. From the SysOp - Note: The solenoid coils are not designed to operate on direct 24 VDC. The ECM sends a 24 volt PWM signal at a duty cycle which provides the necessary current to the solenoid coils. Do NOT activate the coils with 24 VDC (+battery). If you have a DMM capable of measuring Duty Cycle that's the best way of measuring the signal that is coming to the solenoid. In neutral it should be 0%, and with a gear engaged somewhere probably above 80%, but that's a WAG.
Pulled back cover off of trans and took voltage there on solenoids. I believe that was the voltage with the key on not running. Investigating harness from engine Ecm to tcm now.
I'll send you an electrical schematic. Keep an eye on your PMs.
Update. Apparently yesterday tech stalled (put in 3rd gear held break on floor) dozer to build heat to see if injector code would come back. Well he heard a ka-klunk sound after a little while. And that’s why he’s hell bent on it’s not electrical issue. So sounds to me I now have electrical issue and trans issue. Got dozer on slab washed off pulling trans in morning. Btw pulled filters looks like full of clutch discs. Keep y’all updated.