96bulldogpower Posted March 17, 2018 Share Posted March 17, 2018 Hey guys, we just acquired another truck in our fleet however we got this one as a last minute deal as a known non-runner. We had the truck towed to our shop where we began looking through it to see what was wrong. A little about the truck, this is a rare combination because it has a Mack AC engine and a Allison hd4560 behind it, it is a 2005 CHN613. When we got it we found that it would not crank, it was determined that the transmission power fuse was burned out, we replaced the 15 amp mini fuse and the keypad shifter lit up which also allowed the truck ignition to function again to crank the truck. Now that the truck cranks over, it cranks Over just fine. It has fuel but will still not start. There is a 6-4 blink code for “J1939 communication”. Fuse #49 on the epdm does NOT have current which I understand supplies the engine ecm and abs controller with power. The abs controller also does not do its start up test where it “clicks” when you first put the key in the run position to start the truck. I’m looking for help! I have run into a road block with this truck and I know the fix can’t be too hard, just difficult to find. The truck only has 250,000 miles, it can’t be that bad! Quote Link to comment Share on other sites More sharing options...
96bulldogpower Posted March 17, 2018 Author Share Posted March 17, 2018 Update, I checked power at the EECU, no power to any of the pins, there’s is also no power to fuse #49 under the hood fuse panel. In that fuse panel there is power to all other fuses except for #49 which powers ignition and abs, I believe that would explain why abs does not cycle its self test when you put the key in the run position. Inside the cab I have power to all power relays and vecu fuses. Quote Link to comment Share on other sites More sharing options...
96bulldogpower Posted March 17, 2018 Author Share Posted March 17, 2018 Update: found cause of no power to EECU, there were several damaged pins on the bulkhead connector at the firewall. Fuse #49 and abs now have power. Abs completes the test cycle “click” with key on run position. I tested power to the EJ2 connector at the EECU and there is now power to the EECU after repairing the damaged pins on the bulkhead connector. Everything is now live, abs, vecu, and EECU. Unfortunately I’m still not able to start the engine. I’m about to go get ether to try and carefully convince it to start, it has plenty of fuel in the tanks and filters are full of fuel. 1 Quote Link to comment Share on other sites More sharing options...
fjh Posted March 17, 2018 Share Posted March 17, 2018 Thanx for posting your fix! Sorry weren't able to help! Quote Link to comment Share on other sites More sharing options...
96bulldogpower Posted March 17, 2018 Author Share Posted March 17, 2018 Not fixed yet, still trying to get the truck to start. So now that I have power to everything, I realize that the j1939 communications are still not working. The tachometer and the oil pressure gauge do not register anything while the truck runs on ether, the truck will not stay running on its own. This tells me that both the H and L wire (yellow and green wire) on the j1939 are not communicating. I cannot figure out why. I tested continuity inside and outside of the cab and verified the wires and connectors are in good condition. Does anyone have any tips on where to look next? Quote Link to comment Share on other sites More sharing options...
96bulldogpower Posted March 17, 2018 Author Share Posted March 17, 2018 I no longer have blink code 6-4. Now i have blink code 6-3. 6-3 is the only blink code in the system. Quote Link to comment Share on other sites More sharing options...
96bulldogpower Posted March 18, 2018 Author Share Posted March 18, 2018 I still can’t get the truck to start, the oil and rpm gauges don’t even move when turning over. Any ideas guys? Quote Link to comment Share on other sites More sharing options...
96bulldogpower Posted March 21, 2018 Author Share Posted March 21, 2018 Still not luck guys, I talked to my Mack dealership to see if they could help, their response was to purchase all new EECU, vecu, and vmack modules which totaled out to a crazy amount of money for something that may or may not fix the issue. I have blink code 6-3 and engine cranks over fine but won’t start, I’m stuck. Any help would be appreciated. Quote Link to comment Share on other sites More sharing options...
41chevy Posted March 21, 2018 Share Posted March 21, 2018 A 6-4 Code indicate loss of communications between the VECU(Vechile Electronic Control Unit) and the EECU (Engine Electronic Control Unit). If you disconnect the ABS ECU and measure the resistance across the yellow and green wires (J1939 High and Low) you should have 60 Ohms. Make certain the key is off! if you have 120 Ohms the VECU is not seeing the EECU or vise versa. Start at the Bulkhead connector and measure the resistance towards the VECU you should have 120 Ohms, then towards the EECU you should have 120 Ohms. the ECU's must be connected. One side or the other should have 0 Ohms if you are getting this code The grey plug with only 3 post/wires in it coming out of the firewall on the driver side and going down. It will have a yellow and green wire in it. On some trucks it also runs on top of the tranny for hooking up a auto tranny ECM Check there for corrosion and grounds 1 Quote "OPERTUNITY IS MISSED BY MOST PEOPLE BECAUSE IT IS DRESSED IN OVERALLS AND LOOKS LIKE WORK" Thomas Edison “Life’s journey is not to arrive at the grave safely, in a well preserved body, but rather to skid in sideways, totally worn out, shouting ‘Holy shit, what a ride!’” P.T.CHESHIRE Link to comment Share on other sites More sharing options...
96bulldogpower Posted March 22, 2018 Author Share Posted March 22, 2018 Thank you SO much for these tips! I need to go out and buy a new multimeter tomorrow, I will report my findings as soon as I see what’s going on, thanks again! Quote Link to comment Share on other sites More sharing options...
96bulldogpower Posted March 22, 2018 Author Share Posted March 22, 2018 Okay.. well I tested the resistance on the wires today. I had 60 ohms on the abs plug I disconnected. Then I reconnected it and tested both ways from the bulkhead connector at the firewall, I have 120 ohms both ways. I looked all over the harness coming down from the cab and even in between the frame rail and could not locate the three wire plug I did however find a two wire green and yellow connector (had black paint over the wires) but it had a cap at the end of the connector, I found this near the top of the transmission on the driver side frame rail. I believe what I found was a terminating resistor. Here’s a picture: I disconnected the batteries but the truck still has a blink code of 6-3, it turns over fine but refuses to start. could this really mean I have a bad ecm? If so, how would I go about finding out which one it is that’s bad? Quote Link to comment Share on other sites More sharing options...
41chevy Posted March 22, 2018 Share Posted March 22, 2018 (edited) The capped connector shows it never had a trans control module, some do some don't. Seems to point to a bad eecu or vecu . Do not know if they can be checked without the Mack interface tool. You should be getting a MID & FMI besides the 6-3, which will help in your diagnosis. Edited March 22, 2018 by 41chevy 1 Quote "OPERTUNITY IS MISSED BY MOST PEOPLE BECAUSE IT IS DRESSED IN OVERALLS AND LOOKS LIKE WORK" Thomas Edison “Life’s journey is not to arrive at the grave safely, in a well preserved body, but rather to skid in sideways, totally worn out, shouting ‘Holy shit, what a ride!’” P.T.CHESHIRE Link to comment Share on other sites More sharing options...
96bulldogpower Posted March 23, 2018 Author Share Posted March 23, 2018 I’ll call my Mack dealer in the morning and see if they can diagnose computers on their bench, if that’s the case then I’ll pull them out and take them to the dealer to see what they have to say. I’ll report back as soon as I get an update! Quote Link to comment Share on other sites More sharing options...
96bulldogpower Posted March 23, 2018 Author Share Posted March 23, 2018 (edited) Unfortunately I do not have a tech tool to scan the truck, I’m doing my best with what i have. QUESTION.. I have a 2004 cxn613 with the same AC motor, but this one is manual as opposed to the truck with the problem which has Allison automatic.... if i pulled the eecu and vecu from the 2004 and put them on the problem truck, would that work to help me rule out ecm failure? Or would t not even start because it has a different transmission? Edited March 23, 2018 by 96bulldogpower Quote Link to comment Share on other sites More sharing options...
41chevy Posted March 23, 2018 Share Posted March 23, 2018 1 hour ago, 96bulldogpower said: Unfortunately I do not have a tech tool to scan the truck, I’m doing my best with what i have. QUESTION.. I have a 2004 cxn613 with the same AC motor, but this one is manual as opposed to the truck with the problem which has Allison automatic.... if i pulled the eecu and vecu from the 2004 and put them on the problem truck, would that work to help me rule out ecm failure? Or would t not even start because it has a different transmission? I believe different for the Allison, but it may start, probably set codes for no Auto but easy to clear. You have seemed to rule out issues with the harness and connectors.I would swap the VECU first and try to start, than go the next. If it starts puul the first unit you put in ,reinstall the original and see if it starts. Extra work but you can sort of end up replacing only the bad unit. You did check the harness plugs and modules for corrosion at the connector pins, didn't you? Quote "OPERTUNITY IS MISSED BY MOST PEOPLE BECAUSE IT IS DRESSED IN OVERALLS AND LOOKS LIKE WORK" Thomas Edison “Life’s journey is not to arrive at the grave safely, in a well preserved body, but rather to skid in sideways, totally worn out, shouting ‘Holy shit, what a ride!’” P.T.CHESHIRE Link to comment Share on other sites More sharing options...
96bulldogpower Posted March 23, 2018 Author Share Posted March 23, 2018 Perfect! Sounds like a long shot but I’m willing to try anything to get this thing working! Tomorrow I’ll go ahead and swap ecu’s around while my 04 is at the yard. Hopefully it does the trick! And yes, I did check every relevant connector I could find, they all looked clean and dry. ill report back with what I find out by swapping out ecu’s first thing tomorrow! Quote Link to comment Share on other sites More sharing options...
96bulldogpower Posted March 23, 2018 Author Share Posted March 23, 2018 Okay NEWS! I swapped VECU from my 04 and nothing happened, then I swap the EECU and it started!! Then I plugged the original VECU and it still worked. Even the transmission works just fine! This means the truck’s original EECU is burned out! Now I’m going to start looking for a used EECU and hope that my Mack dealer will program it to my VIN. On another note, I thought I’d be happy to hear the engine running... unfortunately now that it runs, it revealed another issue, there’s a sound coming from the engine exactly like when our other truck wiped a cam lobe It sounds like a loud thud coming from one cylinder Although the engine doesn’t really shake as badly as our other truck when it wiped a lobe, and idle isfaily smooth with exception of the thud noise. The engine also blows a medium amount of black smoke when you press the accelerator.. I ran out of time today to mess with it, so I’ll get back to working on it this weekend hopefully, I’ll first remove the valve cover to see what’s going on. Any ideas? 1 Quote Link to comment Share on other sites More sharing options...
96bulldogpower Posted March 28, 2018 Author Share Posted March 28, 2018 I was able to finally pull the valve covers off yesterday and found all of the intake pushrods were bent. The truck has engine brake but the exhaust side pushrods with the spring on them were fine not bent at all. I bought six new pushrods from Mack and installed them this morning, i cranked the truck up still using my other truck’s eecu, and it runs much better now. However there is a very loud “thud” noise still present... the sound is reminiscent of one of my other trucks years ago when it wiped a couple cam lobes. I’m almost certain this truck has a bad cam or failed lifters. When I reinstalled the rocker shaft assemblies with the new pushrods i noticed that at least on two exhaust side rockers there was so much rocker play that the pushrods could nearly come off the socket on the rocker. I ran out of time to work on the truck today but I guess the next step is to remove the oil pan and begin taking apart the front of the engine to pull the cam. I’m not very excited about this job at all, the last time we did an in house cam job parts alone cost us over $2000. Quote Link to comment Share on other sites More sharing options...
96bulldogpower Posted March 28, 2018 Author Share Posted March 28, 2018 By the way... I have the engine’s existing EECU at a ecu repair shop here local to me in Dallas, TX. They seem profesional.. I’ll let you guys know if it works! They claim the ecu will retain the factory data so that I wont have to take the truck to Mack to have it reflashed. They will save me a cool buck if it is successful. 1 Quote Link to comment Share on other sites More sharing options...
fjh Posted April 3, 2018 Share Posted April 3, 2018 I’m almost certain this truck has a bad cam or failed lifters. I Think your correct The spring loaded push tubes indicate that the engine is equip with ceramic roller lifters If all the push tubes were bent it indicates in my mind that the engine was over sped at some point In my mind you need to Replace ALL the lifters! This Ain't gona be cheap! 1 Quote Link to comment Share on other sites More sharing options...
Micilk Posted November 7, 2019 Share Posted November 7, 2019 How are you. I have the same problem. you will have some diagram with which you can guide me Quote Link to comment Share on other sites More sharing options...
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