When Rocky first called me he told me he had bought a 98 379 with a 2002 Series 60 two months ago that he wasn’t happy with it. He said his Pete didn’t have much power, averaged 4.2 mpg, would de-rate without warning, and wouldn’t stay at high idle for long without dropping down to idle for no apparent reason. Rocky suspected his DDEC ECM was the problem and wanted to see what I could do. He was scheduled to unload a reefer trailer full of cheese at 5:00 p.m. the next day in Bedford, Pa. and wanted me to pull his DDEC IV to change the battery, seal, and re-rate the engine to 600 horsepower at 2400 rpm. He also couldn’t drop his trailer. I told him that even though I’m not set up as well as I’d like for field service work what he wants to get done shouldn’t be a problem as long as everything else on the truck is ok. All I would be doing would be taking the ECM off, doing my thing, and putting it back on. It was unusually warm the morning of January 10th 2016 and the high for that day in Pittsburgh was 50 degrees. There I was, 6:00 a.m. on a Sunday pulling Rocky’s DDEC IV ECM off his engine at a rest stop just off the PA turnpike. With Rocky’s DDEC in hand we left his truck and drove to the DCS ECM dyno so I could get to work. After powering it up we saw that the DDEC IV had over 1 million miles logged and it wasn’t the original ECM this 02 Series 60 had on it from the factory. After backing up his 430 program, load testing the injector drivers, and checking his internal ECM battery I told him I couldn’t find anything wrong with the ECM. It didn’t even need a battery. The only thing I found that could explain his de-rates were multiple counts of low coolant level logged in the memory. He said the truck had plenty of coolant so a wiring problem with the coolant level sensor was probably the true cause of the de-rate issue. After re-rating his DDEC IV on the ECM dyno I grabbed my soldering iron and got ready to head out. When Rocky and I stepped outside we saw that the weather had taken a turn for the worse. The sky was blue but the wind blew in freezing gusts right through my jacket like a cold day in the mountains at Breckenridge. Rocky suggested I bring my 7.3 Powerstroke F-350 just in case his truck needed a jump. I felt like Rocky might know something I didn’t but I made a joke about my own truck to make him feel a bit more at ease. If we can get my 7.3 started then your Series 60 should start no problem. He mentioned that he planned on getting new batteries as soon as he gets back home but he feels they might need replacing soon. When we got back to his truck I installed the DDEC IV while Rocky hooked up jumper cables between my truck and his. The volt meter on the dash fell to less than 8 volts when I hit the starter button but the Series 60 started in about half an engine revolution. The engine still had some heat in it from the morning.
While the engine was idling I plugged into it with laptop and saw the low coolant warning was still active. Rocky and I got out and opened the hood. He topped off the coolant while I looked at the harness. I found two butt connectors in the coolant level harness that were in terrible condition. Rocky told me he had to leave to make his delivery time in about two hours. We had planned on using Rocky’s 1500w inverter to power my soldering iron to make repairs to his coolant level harness, his check engine light, and his low coolant light but now I was having my doubts. If these repairs weren’t made he would still have a de-rate and the program wouldn’t perform. He would be in the same situation he was in this morning, stuck in a de-rate because of a coolant level circuit issue. Looking back we were pushing our luck but we both wanted the same thing. Go big or go home. That kind of thinking can get you in trouble sometimes. I didn’t want to risk shutting down the engine while soldering and pulling all that current from his batteries so we left the engine idle while we pulled the dash panel. While the engine was idling we turned on his 1500W inverter and I plugged in my soldering iron. The soldering iron’s LCD display was on and reading temperature but I held the tip in my fingers and it never got hot. I used a torch to boost the temperature of the soldering iron and soldered a few burned out traces on the back of his dash panel. After I was done we started to set the dash back into place but heard a pop and the engine stopped. The ignition circuit had made contact with one of those mystery wires the previous owner had that ran to ground. I reset the ignition breaker and tried to restart the engine but it was too late. The voltage was too low and all the engine would do is crank. There was no smoke from the stacks and every time I hit the starter button the dash lights would reset as if I cycled the ignition, LEDs flashed like strobe lights, and the fan solenoid would release air and lock up the fan clutch. I used to have to start cold trucks every day and I know just what they do when this happens. I didn’t need my laptop to know what was going on but I plugged in anyways because I wanted Rocky to see what was happening. The ECM shuts down the instant voltage gets too low. As soon as this happens the fuel injectors shut down as well. After that it doesn’t matter how much you crank the engine. It’s not going to start without fuel. For Rocky and I, it didn’t matter that the engine wasn’t cold anymore. The ECM would shut off just like I turned off the ignition myself as soon as I hit the starter button. As soon as you recognize this is happening stop cranking the engine. Save your battery voltage and inspect the battery bank, and start thinking about getting a jump. When Rocky and I lifted off the step covering the battery bank we saw that one of the batteries looked fat. This means that the battery has a major issue and is likely killing the rest of the battery bank. Too bad for Rocky and I it was a Sunday and no Pilots, Flying Js, or Walmarts had his battery in stock. 5:00 p.m. had come and gone and Rocky had rescheduled his delivery for Monday the next day. Rocky and I cleaned all the terminals in an attempt to get his truck started but with only three tired batteries left in the battery bank and my truck acting as the battery charger it just wasn’t enough. So there I was Monday morning installing a new set of batteries from Cummins Bridgeway. The wind had died down and the temperature dropped down to about 8 degrees. It had been about 18 hours since the Series 60 shut down. As I held the starter button down and looked up at the stack I realized Rocky and I were going to experience another cold start problem of a different flavor. The engine was failing to start but this time things were different. After I released the starter button a haze of white smoke trailed out of the downwind stack. This is a sign that can indicate a mechanical issue with the fuel system or low compression. It’s just as important to understand what an ECM cannot do as it is to understand what it can do. There are many things that cannot be diagnosed or repaired with a laptop. Detroit Diesel later found a blown o ring in a fuel check valve and lots of air in the return. With over a million miles and no record of an inframe or injector replacement there are a few possibilities here as to what’s going on but that is a subject we’ll talk about another time.
Fernando DeMoura, Dieselcontrolservice.com