Bump Keys and Blind Robins?

 

Steve loves the American Pickers’ show. He lives on the edge of Summersville not far from the Monongahela national Forest. He makes a living using his Sprinter, a vehicle he acquired at a government auction at a decent price. Steve collects pieces of the past and sells them to antique dealers. He also hunts meteorites and micrometeorites. Steve tells me that he fastens a couple of magnets over the downspout of a rain gutter, so that rainwater flows over them. After a couple of weeks, he finds tiny particles sticking to the magnets. They’re remnants of meteoroids that disintegrated in the upper atmosphere. He sells the ‘space dust’ to collectors.

“As soon as I got this Sprinter, it started to do some strange things. I was looking for memories, cruising around to old barns when the auto headlights turn on, then off, but only once. That night, the auto headlights decided to turn off so I used the manual override. The service light also turned on. Then the ‘door ajar’ light came on, blinking as the door locks cycled on and off.”

I wrote all of the data down. “Anything else?”

“Yeah—the battery goes dead if I let the vehicle sit a couple of days. I took it to several shops but all they did was threw some parts at it. Every time I take it somewhere, the Sprinter behaves, like there’s nothing wrong. Then it acts up after I get it home.”

The vehicle had no known work history. “I heard that it was used as a surveillance vehicle in another life.”

I performed the usual steps: a visual inspection, during which I found a “bump key” in the vehicle. It didn’t belong to Steve so I added the bump key to my collection of jiggler keys. All of the modules were communicating and there were some communication DTC’s, which didn’t surprise me. Parasitic drain on this vehicle was 30 mA, not bad for the Sprinter. Steve and his partner Jeff worked with me on the vehicle. Despite the three of us performing diagnostics, evaluating connectors, scoping the CAN bus, performing ground credibility checks, we came up with nothing. I even used my CAN Bus Shield Interface connected to my laptop but saw nothing unusual on the data bus.

“This was used by the Feds—maybe there’s a hidden tracker somewhere,” Jeff joked. I wasn’t laughing. You can detect some GPS tracking devices by the electromagnetic radiation they emit. They can generate a pseudo-random digital noise source used to correlate against the data received from a satellite’s transmitted Coarse Acquisition data stream. By looking for unintentional radiation of the digital noise or its harmonics, you can pinpoint the location of an operating GPS receiver.

All you need to do the detecting is use a noise sniffer—a cheap AM radio. You need to tune it to the noise. Remember, the “noise” I mentioned isn’t truly noise. The GPS codes include Coarse Acquisition and P-Code. The code streams are made up of zeros and ones—bits or chips. They are noise-like signals but the fact is, they’re generated using a mathematical algorithm.

After you tune the AM radio, add a drop of glue to the capacitor’s tuning post to prevent frequency drift. You have to maintain the radio’s ferrite rod antenna in a horizontal position, with respect to your body, when using the sniffer.

“Where did you learn how to do that?” Steve asked.

“On the back of a cereal box from the 1960’s,” I replied. When I started the Sprinter and a vehicle speed signal was acquired, Steve, Jeff and I took turns using the sniffer. Steve found a hot spot in the dash. We drove back to his farm and I used my inspection camera to search inside the dash.

The squawker looked like a switch cover but Jeff was right. It was a GPS tracking device powered by a bobbin-type lithium thionyl chloride tied into an ignition-feed circuit.

“Wow, Steve—is your wife keeping tabs on you or something?” Jeff said, looking at the unit. It was really sophisticated. We figured the device was used to track the Sprinter in the event that it got stolen. Or maybe it was used in some sort of sting operation. It was interesting that I found that bump key.

“I have to work with some folks in Langley next weekend,” I said, “I’m going to take this tracker to see what they think about it,” I said.

“They might arrest you and throw away the key,” Jeff said.

Steve found a lunchbox, opened it and handed me a sandwich wrapped in wax paper. “What kind is it?” I asked, noticing the aroma even through the wax paper.

“That’s an onion sandwich on rye with a generous smearing of garlic butter,” Steve said, removing the wax paper from his sandwich.

“No thanks,” I said, putting the wrapped sandwich back in the lunchbox.

Jeff laughed. He handed me something wrapped in cellophane. “Well then, how about a package of blind robins, Bob?”

“Ever hear of those?” Steve asked.

“I sure did,” I said, remembering my childhood memories. I couldn’t believe it.  I remembered my father buying those at the bait shop and the neighborhood bar. Jeff waved it under my nose. “Smoked and salted,” he said.

“They’re a big around these parts,” Steve said. “Some place by the Ohio River cleans the herring, smokes them, and highly salted with the heads and tails still on. Once the bones fall out, he chops off the heads and tails and puts them in these cellophane packages.”

“They make for a good beer snack,” Jeff said. I passed on the blind robins. I ate them as a young boy but my digestive system today would tolerate them about as much as it would tolerate the onion and garlic sandwich on rye.

“Just pay me and I’ll be on my way, Steve.”

They both milked my hand, thanking me and invited me back to do some fly fishing.

And that was that. I left Summersville and decided to eat “regular food” at a drive-on off the beaten path.

Until next time.



I do a little fly fishing when I have an opportunity. Some anglers consider the Elk River one of the best trout streams in the Eastern U.S. It has native Brook trout, and plenty of wild Brown and also Rainbow trout. It is 248 miles from my house. You take 77 south and catch 79 out of Hillsdale. I wasn't going quite that far. A friend of mine has a trucking company near Big Chimney.

He said that "They threw everything at one of his trucks including the kitchen sink. This truck had issues with the dash, the gauges would go dead at times and had the following codes:

SID 251, FMI 4; SID 231, FMI 9; SID 231, FMI 13; SPN 639, FMI 9; SPN 639, FMI 13.

"The ECM was replaced, as was the VECU," Larry, the owner said. His technician, Dale Richmond, was also there.

"Is the VECU new or is it a reman box?" I asked.

"Brand-spanking new," Larry replied.

"Anything else?"

"I installed both terminators. There's no communication with the brake ECU, SRS ECU and the VECU. Oh--and I fixed a broken ground near the starter."

I wrote it all down. "Is that it?"

"I found 160-Ohms on the ground for the ABS/ECU, cleaned it up and used Stabilant-22."

I noticed that the multiplex DTC's would go inactive every 45 seconds and then went active for 5 seconds--strange.

"One of the guys said the pitch of the twist in the wiring could be wrong. Or that we should change the terminating resistance."

"Don't do that. Keep the terminators as is."

"Why?" Dale asked, "Why do they put the terminators where they do and why keep the value the same?"

"Because of Electromagnetic Compatibility," I said.

Dale turned to Larry. "In other words, boss, he doesn't know."

"Firstly," I said, examining the fuse box, "Both terminating impedances have to be balanced between the two wires' terminating ends and matched to the characteristic impedance so as to minimize signal scatter when high baud rates are used. Secondly, both wires must individually present the same impedance with respect to a signal ground and also to a shielding ground. Thirdly, both cables must have the same exposure to the interfering intrusion."

I looked at Dale. "Need I go on, my friend?"

"Nope."

"On this truck, the VECU controls the multiplexing. Can I assume that you checked the fuses and the wiring?"

"Yeah," Dale said.

  I checked the fuses and F81 had no power. Dale couldn't believe it. "Well, it had power when I checked it."

He grabbed the test light. It lit, indicating continuity across the fuse. "See? You must have had a bad connection or something."

I checked it again with the same test light. It did not light. Dale grabbed it and checked it again. It illuminated. He laughed, handing me the light. "I guess you Ohio boys talk up a storm with that technical garbage but you can't do the hands-on, eh?"

I started pulling the fuse panel.

"What are you doing now?" Dale asked.

"Look how the gauges are fluctuating," I said, "There's something going on with F81."

Sure enough, on the backside of the fuse box was a fleet tracking device. "This could be a problem," I said.

"The guy that installed it knows a lot more than you do," Dale said. I didn't know what his problem was, but I started to remove the case. "You know, I do electronics," Dale said. Alphonso and I designed that FTR and he knows more than anybody.

"Then why don't you call him?" I asked.

"He went out of business," Larry said.

I examined the circuit board. "We used a solid state relay and latching relay combination in parallel driven by different pins, as you can see. The SSR is powered up just long enough to switch the mechanical relay and then we switch the SSR off."

Wow--Dale impressed me.

"So, do you see anything unusual, professor?" He said that mockingly.

"Are you using an AC load in the circuit, Dale?"

He chuckled. "Of course not--you should know better than that, professor."

"Well, ace, the solid state relay you guys used is meant to switch AC loads only."

Dale's eyes widened. He looked at the SSR. "This relay won't shut off until the zero crossing occurs. Because you are using it on a DC load, then it stays on once switched on and will not turn off until the current goes to zero. It's putting just enough current into Relay RLY04 upstream to cause distortion."

I de-soldered the PCB SSR and scavenged one from Larry's scrap parts box, found inside a PDC box. I soldered it in place, checked the circuit. The dash functioned normally, the DTC's were gone and now I could test fuse F81 as well as Dale could.

Larry was thrilled. "Son-of-a-gun--let's go to dinner. It's on Dale," Larry said.

"Want to work full-time for me, Bob?"

"Nope--I'm 65 years old, I do this because I like it and if I do it for a living I'll hate it."

"Well, then, come on down and we'll do some serious fly fishing."

"Yeah--and we could do some canoeing," Dale said. Right when he said that, I thought about the movie "Deliverance."

"I'll pass on the canoe trip."

Oddly enough, the radio station I was listening to on the way home played the Dueling Banjos song. Creepy.

 

 

 

 

Knowing How to Learn

Quite some time ago I was teaching an electrical class to a group of young adults. I asked them to name the most powerful force on earth. One said the power of a hurricane. The second thought a blinding snowstorm in Antarctica. The third suggested a hydrogen bomb. Another said the Internet, because you could find the answer to everything.

“It’s not any of those,” I said. “I think the force with the most power on earth is knowing how to learn.” With knowledge, I could find shelter in a hurricane, and that made me stronger than the wind. I would know how to stay warm, and that would let me defeat a blizzard. With knowledge, I could build a hydrogen bomb, but I could also dismantle one and get rid of it.”

“But what about the Internet? I can learn a lot. I can find the answer to just about everything,” the student said.

“So true,” I said, “But knowing how to learn and how to use that knowledge gives you the power to deal with change. When you embark on your career you will face many challenges and opportunities. Knowledge is your key to your future. If you know how to learn, you will be ready for almost anything.”

The students asked me to elucidate.

“Anything you don’t understand is a mystery, waiting to be solved. For example, you might not know how to diagnose the cause of an engine stumble; or why that fuel injector won’t fire. It’s a mystery to you. You could decide to look it up on the Internet and find 10,000 answers. But you would have to sift the right answer from the wrong answers. If you wanted to figure out why that injector doesn’t work, you need some clues. A good diagnostic detective knows that.”

“How would you figure out what’s wrong with that injector?” A student asked.

“Use your eyes and ears to scoop up clues. Look at that injector; figure out how its gets power. Look at the wiring and the fuel line that connects to it. Does it look like it’s been tampered with? Look for witness marks on the connector and line. Learning by observing is important.  Practice using your other senses, too. Listen to the injectors with a mechanic’s stethoscope. Listen how that engine is running. Do you smell fuel?”

Looking and listening was the point I was trying to make to them.

“When you’re in school, ask your instructor how something works. When you are curious about something, ask. Instructors are willing to share what they know. There are no silly questions. No questions are too simple. Questions are stepping stones to knowledge. Unless you ask, you may never know the right answer.”

I wanted to make sure they realized the importance of asking questions.

“Another way of knowing how to learn is by reading. Your college books contain the combined knowledge of decades of experience, written by manufacturers and experts in the field. Reading is a doorway to discovery. Read, read, and read some more. It will expand your mind and fill it with new ideas.”

“What about learning by doing it?” A student asked.

“There’s a good chance you already know how to ride a bicycle,” I said. “Do you remember how you learned? Maybe you saw somebody else riding and thought you would like to do that, too. So, you climbed on a bike, started pedaling, and fell over. You got back on and fell over again. You wouldn’t give up, though, and slowly figured out how to ride. Today, riding may be so easy that you’ve forgotten it was ever difficult.”

I was getting to them. They were taking notes. “Much of learning is like that. You try something and grasp a small chunk of it. You try again and understand a little more. The key is to learn from your successes and your mistakes. When you master a skill that way, you can use it for the rest of your life. You own it. It’s yours and no one can ever take it away from you.”

I continued. “Look for chances to increase your knowledge. Instructors and books have much to give you. Develop good study habits and then use them. The hardest part of seizing opportunities may simply be getting started.”

“It sounds challenging,” one student said. Others agreed.

“It is,” I said. “But map out a route to reach your goal. Determine what small steps will take you there. Then go for it. But nothing will happen unless you make it happen. You got to get up from that chair and get going. Open your book and see what it says. Open your mind and see what you can put into it.”

“What about the students who really are struggling with tough times in life outside of college?” One asked.

“Rain falls on everyone,” I said. There is not much you can do about that. But you can decide to see storms as opportunities rather than obstacles. You can choose to make the most of a situation rather than giving up and wishing you were somewhere else. Overcoming tough times builds your ability to meet future challenges. Challenges are great teachers when you let them be.”

I gave them one final comment. “If you want to see life as full of opportunity and excitement, it will be. The choice is up to you.”

Keep on Truckin'!

 

 

Big Jake Clayworth has been driving trucks for just this side of 30 years. He gets up about 5 am, gets some coffee at the truck stop, walks around his rig to inspect the tractor and trailer and then does his logbooks. He checks the road conditions and weather and then it's on the road for him. He might do a drop and hook or a live-load or maybe a live-unload. He's worked for a few of the major trucking companies out there.

They put Jake into a Peterbilt 386 with Cummins ISX CM871. "It started acting up two weeks ago," Jake told me, "It cranked but wouldn't start. Fan clutch solenoids would cycle on and off with the key on and the lift pump was making noise."

Basically, how this system works is that sensor inputs are fed into the chassis node where the info is processed and delivered to the CECU by way of the CAN data bus. The chassis node also controls various relays (trailer turn signals, stop lights, backup alarm, turn signals--you get the idea).

"I made the mistake of taking my rig to a real hack," Jake said. He smoked some computers and wires."

"Have you tried Smokey's Wire and Component Smoke?" I asked, but Jake wasn't in the mood for joking.

"I get paid 43 cents a mile--those are paid miles." What Jake meant was that they weren't" practical miles." It's miles paid "how the crow flies." He wasn't getting paid for down time.

 

Whoever replaced the chassis node on this truck didn't follow procedure, for one. You have to disconnect the batteries while replacing a chassis node. You should only reconnect the batteries after everything is reconnected. You also need to simultaneously supply power to the new chassis node and CECU during the first power cycle or else a fault will be triggered and logged on the DIC when the CECU detects that communication of the chassis node is corrupt.

 

"You can't just cycle the ignition because the parameter file is transmitted to the chassis node only when you complete the battery power cycle," I said. You have to cycle battery power directly at the batteries. Disconnect battery power for about a minute during the power cycle to allow power-down.  On a J-1939 backbone, DTC's consist of a Source Address (SA) identifying the ECU sending the code (SA0 = Engine ECU #1), a Suspect Parameter Number (SPN) which identifies the PID fault code error message and a Failure Mode Identifier (FMI) identifying the type of fault. Jake's Peterbilt was loaded with codes.

 

I turned the key ON, started the ESA and established communication with the vehicle while Jake watched. His Zero-dollar-clock was ticking fast and he reminded me of it.

 

"I need a drink of Doctor Knucklebuster's Diagnostic Liquid to help me out here, Jake."

"Considering what I'm paying you, you should be able to by a solid gold magic wand, you think?"

 

"Ouch." Jake wasn't a happy camper. He was plagued by Pavement Princesses bothering him at the last truck stop. "I know that Lot Lizards are earning a living, but geez, they are getting worse," Jake tells me. "That Sleeper Leaper was busier than a cat covering crap on a marble floor."

 

Okay, Jake--I found a DTC 148309 stored--which tells me that CECU can't read messages from the engine on V-CAN,"  I said.

 

"Which means what?" Jake asked.

 

"You could have an open or a short in the wiring from the CECU to the engine ECU. You might have a terminating resistor issue," I said.

 

"Well, that would make a bishop mad enough to kick in stained glass windows," Jake said.

 

I did some rapid-fire diagnostics and won't bore you with the details, but I found an issue at the Steering Angle Sensor (SAS). This Peterbilt uses a Meritor Wabco SAS that is SUPPOSED to have a jumper wire between terminals #2 and #3 that connects CAN Low to CAN high. The terminal at Pin #3 had poor tension. After that, and a few other checks and repairs, I did the SAS calibration procedure with my Meritor Wabco Toolbox software on my Toughbook. By the way, the terminator value in the SAS is 180 Ohms.

 

"All fixed, Jake. I had to replace some wiring from nasty wiring repairs that hack did, but you are good to go."

"You know, when the Lord was handin' out brains, that fool thought God said trains, an' he passed 'cause he don't like to travel."

 He showed me another truck to work on. "This one's an old Pete 379 with a Detroit S60. The hack said he couldn't find anything wrong with it."

This Peterbilt had an ECM and a cab-mounted, Wabco ABS ECU. I measured 131 ohms on the data link. The terminator near the left hand cab mount had been eaten alive by corrosion. I replaced it, installed a sacrificial anode and measured the resistance of the parallel terminators: 62.2 ohms.

 

Jake was thrilled until I handed over my bill. "No offense, Bob, but I hope I don't see you again for a while."

"None taken, Jake. Watch out for those lot lizards."

 

 

 

 

 

 

The Case of The Puzzling Enclave

 

 

While driving home on I-70 at Dallas Pike, I stopped for supper at a TA facility of Exit 11. I was headed back from an interesting diagnostic investigation in Pennsylvania and encountered another in the parking lot. A technician was working on a 2011 Buick Enclave and I decided to join her.

"What's up?" I asked, watching her read the data with a scan tool.

She mentioned that she was from a shop west of the truck stop and was taking the Enclave on a road test. "Do you know anything about diagnosing vehicles?"

"Just a little," I told the young technician."

"The Money Indicator Light turns on intermittently," Helen said, "And there is a P069E that sets in the ECM and a P2534 in the Fuel Pump Control Module. The vehicle came in for an oil change and tire rotation. Less than a month later the customer brought it back for this. The FPCM was replaced twice."

"At least you know what it isn't," I said. I couldn't resist. Helen didn't seem to appreciate it.

"There are no aftermarket components on it," Helen said.

I knew that the FPCM got the commanded fuel pressure message from the engine controller and the FPCM sends a PWM signal to the fuel pump. Pump speed was changed by varying the signal's duty cycle. Helen was prepared. Wiring diagrams and diagnostic charts were on the passenger seat.

"If there are codes set in the FPCM, then the FPCM will request the PCM to set a P069E," she said. "And since the P069E is an information only code, I did not change the FPCM because of it," she added. "But the other code--the P2534--sets if the ignition is less than six volts on the pink wire going in to the FPCM."

"That would be circuit number 439," I said.

"Right--an every time I tested it at the FPCM connector, referenced to ground, it read about 12.47 volts."

"That sounds normal," I said.

"And the service information stated that if all circuits tested normal, the FPCM should be replaced. I replaced it and programmed the new module but P069E returned as an active fault in the PCM and P2534 returned as an active code in the FPCM," Helen said.

"There is a free website where you can enter the VIN and---" She interrupted me.

"Been there, done that," she said. "I also checked the Safercar.gov website and ran a VIN search with no results."

Helen was thorough. I estimated that she was in her early twenties, so she didn't have much experience; but she was thorough. "Did you attend a technical college?" I asked.

"Yes, back in Pennsylvania. I graduated the highest in the class," She said with pride.

"It shows," I said. "I've got a factory tool in my car--how about we try it on this vehicle?"

"You've got a Tech2?"

She even knew the name of the old GM factory scan tool. "I'll be right back."

I gave the Tech2 to her to use. To my utter amazement, Helen pushed the buttons on the Tech2 so fast that her fingers were a blur.

"Wow--I take it you've used it before?"

"No, this is the first time I've had one in my hands."

"Then how can you push the buttons faster that I could ever hope for?"

"Are you kidding? Video games are my life when I'm not in the shop. I don't know what I'm looking for but I can move through all the menus pretty easily," she said.

"Go to the FPCM Data List," I told her. She was there before I could take in another breath. I spotted a data PID that wasn't right. "The Ignition 1 voltage is indicating zero volts," I said.

That was Circuit #439, Pin #11, at the FPCM.

"It should be battery power, right?" Helen asked.

"Right," I said.

Helen grabbed a voltmeter, crawled under the rear of the vehicle, and accessed the connector to the FPCM. "I'm reading 12.51 volts at pin #11, she said.

That didn't make sense. The data PID on the scan tool indicated zero volts but the pin at the connector read battery voltage, what it should be. Yet the FPCM saw nothing. Service information indicated a new FPCM was needed.

"We need to check one more thing," I said.