She paid their fee with glee, happy to get the Crossfire back, but almost immediately she discovered a new problem. There were times without warning when the car wouldn’t crank (no starter operation) sometimes and when it took one of those spells, nobody could get it started. Then, just as suddenly, it would decide to crank. At other times the Crossfire would just die going down the road. Further, she said she might drive it a month with no issues and then have a lot of trouble in a single week.
This is the 9 pin connector that feeds power and ground to the PCM, and it is very odd that Chrysler posts the pinout of the PCM side rather than the connector side. The white connector shell is a mirror of this shop manual image, and it’ll throw you if you don’t catch that early.
Were both of these problems related? A problem in the antitheft system might cause the no-crank, but it wouldn’t cause the stalls while driving issue. And because the Crossfire expert who installed the engine no longer was in-house at the first dealer, she decided to take it to another Chrysler dealer about 50 miles away, where she was charged a lot of money for repairs that left the problem untouched. So it wound up sitting in her garage for a while, because she just didn’t trust it.
The Crossfire came to us on a roll-back as a no-hurry troubleshooting job, and it was dead when it got there. Perfect situation, if the problem would remain long enough.
These modules are all on the same network, yet they communicate with the PCM over different pins at the DCL. One of them might be causing this problem, but if so, it’s extremely intermittent.
On this platform, the Powertrain Control Module (PCM) triggers a Pulse Module to control starter engagement. When the engine starts, the pulse module interrupts starter operation — German designs are big on that point. But that module couldn’t make it quit going down the road, could it?
An Identifix search revealed 11 failures of the pulse module causing no-cranks (and one PCM), but my problem was that even if the starter was engaged artificially with the key on, the engine would spin but wouldn’t start. Further, the PCM wouldn’t talk during this time. Could the pulse module cause no-com? Maybe. There are five other modules sharing the Controller Area Network (CAN) B network on this car, but we decided to check powers and grounds first, and that was probably a mistake.
I just loved getting the shipping box back with this label on it after they plainly indicated over the phone that they could rebuild the Crossfire’s PCM. As it turned out, rebuilding the PCM would have been a waste of money.
A diligent check of the PCMs powers and grounds at the C5 nine pin connector revealed that the PCM had everything it needed (as far as we could tell; the only decent wiring information we could find was in Identifix) but the PCM was still asleep. So I had my parts guy call CARDONE to see if it could rebuild the PCM. They answered in the affirmative, but when we sent them the unit, they immediately sent it back and said they couldn’t rebuild it. I also found that you can’t just get a used PCM for this one from a salvage yard and reprogram it. You have to buy a new one, which burns through $2,000 in the blink of an eye. We didn’t need to snag a new PCM on a whim for this Crossfire, at least, not without further testing.
Reconnecting the PCM for the additional testing after receiving it back from CARDONE, we found that the Crossfire fired right up, and we couldn’t get it to stall or fail to start any more. Of course, by the owner’s testimony, it might take a month. But then, we kept it for about a month, checking it periodically with no reoccurrence. We could plug in a Diagnostic Link Connector (DLC) recorder (I have two), but if the network goes down or the PCM stops talking, the DLC recorder is pretty much worthless anyway. I needed something that could be hardwired to record some channels independently of the vehicle network.
Here’s the Pulse Module, which, according to Identifix posts, is usually the cause of no-crank issues (11 out of 13 posts). But I can’t for the life of me figure out how it could cause the Crossfire to quit while driving.
I installed the four-channel Hickok Flight Recorder. It checks the battery, one auxiliary input (I connected this to the hot at key on feed wire), senses spark with a dandy antenna strapped to or near a plug wire and hard wired it to the pulse side of one injector. We might get useful data from these four, or we might not. Snaking the long trigger cable into the car, I mounted the yellow pod with its red button and gave the owner instructions: If and when the car failed to start or stalled while driving, she was to press the button and capture a recording, which I could upload to the computer and hopefully analyze the data. I put her back in the driver’s seat, and two days later she told me it had failed to start and she had made two recordings. She’d let it sit and try it again the next day.
It started that next time around, and she made me a snapshot of the normal start. I had the Auxiliary channel sampling pin 9 on connector C5. That one gets hot when the Engine Control Relay energizes, but that relay is hardwired into the Relay Control Module, which is a $400 item that rides right next to the PCM in the isolation box behind the passenger side shock tower. She green-lighted the repair and all was well. Did this failure have anything to do with the engine swap? I can’t see how.
This is the Hickok Flight Recorder. This Crossfire had been doing so well for so long that I figured I’d monitor battery, feed to PCM connector C5 pin 9 from the Engine Control Relay, fuel injection and spark. If and when it happened again, she pressed the red button on the little yellow pod I clipped on the ashtray; it recorded 15 seconds before and one minute after the button press. I wish it had more than four channels, but we only needed one this time.
The Ones That Make Us Look Bad
Ever had one of those jobs that made you look incompetent when you were absolutely sure you weren’t? When I worked at the Ford dealer, an LTD came in for a transmission service. The car was clean and in good shape, and the transmission a seasoned transmission guy did the service. In those days, we always test-drove every car before performing a requested transmission service; some customers tended to bring in a car with transmission problems, have it serviced, and then claim the service caused the problems.
Well, this one wasn’t one of those. It belonged to a close relative of mine, and it was a straight-up deal. The bill was paid and the car left, but before it was 500 yards from the dealership driveway, it was pouring transmission fluid like an inverted crimson fountain. She limped the car back to the dealership for what seemed certain to be a record-breaking comeback. Because she was my relative and the transmission guy was swamped, I raised the car up on the lift and found that one of the steel transmission cooler lines had split at its roll crimp (the one on the line that snaps past the retainer). My conclusion was that there was absolutely no way on earth the transmission service could have caused that – those lines were six inches north of the transmission oil pan. I repaired the line by cutting and double flaring it and installing a different fitting in the transmission and refilled it with fluid. Even though the failure wasn’t our fault, there were no additional charges to the customer.
The recording on the left is a normal start. She actually made this one a day later than the one on the right. Notice that the auxiliary channel stays low on the right hand recording and that the spark and fuel injection were also offline. She told me the Chrysler dealer had already replaced the ignition switch, and the wires checked out. The root cause turned out to be the Relay Control Module.
Another one of those face smackers was a 1994 Chevy pickup with TBI and HEI that would start, run a few seconds and then die virtually every time it was started cold. After a few of those start and die cycles, it would manage to survive and drive, and our diagnosis led us to check fuel pressure after an all night cold soak. The fuel pressure would kick up to 13 psi on startup, but then would drop all the way back to zero and the engine would die. We saw it do this about three times before it finally survived and the pressure stayed. Further checking showed that the power to the pump was constant during these maneuvers – the pump never lost power, it just shut down after running for a few seconds. I had never seen a fuel pump do this before, especially not this consistently and never on a cold truck, but our diagnosis was solid. This one needed a pump, and we put one in it with the customer’s approval.
The next morning, having parked the truck outside, we went to start it just to make sure it was fixed, and found that it wouldn’t start at all – and this time there was no spark. What the heck? Five minutes later our DVOM revealed that the pickup coil in the distributor was wide open – no continuity at all. Seriously? When you call a customer and explain that he now needs yet another part and more work after having told him he needed a different part the previous day for almost the same concern, well… You find out how much that person trusts your troubleshooting and your judgment. This guy didn’t blink an eye, and we had the Chevy back on the road before 9.
This is a mystery I’ve yet to solve – how this Geo Tracker could ever have had operational air conditioning just blows me away (no pun intended). Virtually every other part of the A/C system was in place and had been ever since this vehicle had been assembled new, and the connector that should have plugged into this switch was stiffly pointing in a different direction like the wires had never been bent to plug into the omitted switch.
This Stuff Doesn’t Make Sense
Another mysterious situation was one I wrote about a while back. A 2003 Explorer had a lot of bearing noise in the rear. This one has an aluminum differential housing mounted to the body and CV axles carrying the torque out through stand-alone two-race bearings to the hubs. We applied the Chassis Ear® to the differential and hubs, found the preponderance of the noise coming from the chunk and tore it down to find pitted bearings. We replaced the bearings, got the rear end set up and reassembled, and had less noise but still too much, and further listening pinpointed noise in the hub areas. When we removed those bearings and found that they were pitted too, we found ourselves wondering how all the bearings in the rear end could fail even if they’re not swimming in the same oil. Well, that one has been running quietly ever since.
Then there was the Camry Air Conditioner anomaly. Even with the right refrigerant charge, that one wasn’t cooling, and with the compressor pumping, pressures on both sides were low, which points to an expansion valve problem. We replaced the expansion valve, which didn’t change a doggone thing. The next logical step was to determine whether or not the evaporator was clogged, but it seemed to flow freely when we put air through its piping. Not knowing what else to do, we replaced the evaporator, and this time we saw normal pressures and a frosty cold register.
Finally, we all like to disassemble failed parts to see what the heck caused them to fail. We learn things that way. Usually the plastic gears loose teeth, but in this case, a tribe of ants had set up housekeeping in this Ford Expedition blend door actuator. Not a single ant survived – and neither did the actuator. There were no visible ants anywhere else in or on the vehicle. They all seemed drawn to this cavity. These little critters tend to foul up relays too.
Speaking of HVAC, some folks might remember the really mysterious situation I encountered about 10 years ago on a Geo Tracker where the girl told me her air conditioner had been working fine at the end of the previous hot season, but winter had come and gone and now her air conditioner wasn’t blowing cold. We went through a lot of circuit testing on that one and finally discovered that there was no button on the dash to engage the A/C. The instrument panel was set up as if that vehicle never had air conditioning – ever. There was a blind plug (one of those you have to break out to install the switch), and the wires leading to that blind plug were stiff and straight and had never been plugged in to anything. The Tracker had factory air – everything else was in place except that switch.
How the A/C had worked previously was totally outside my realm of understanding. I even asked her if any of the dash panel parts had been replaced, and she shook her head. I asked her about the button – had it ever had one? She couldn’t remember anything except that the air had worked fine the previous hot season, which was equally odd. At any rate, the switch was $70, and she didn’t want to spend the money, so we simply jumpered the two wires that would engage the A/C, and any time she turned on the fan in any air mode position, the compressor was running, which doesn’t hurt a doggone thing. It wasn’t a factory-approved fix, but the customer was satisfied.
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