Looking for some insite here. Got a 2011 321d with a C6.4. Sat for 2 months and has a Cranking no start with no fuel coming out of the high pressure pump. I Swapped filters and primed the system still wouldn't start, ran a line from suction side of pump into Jerry can of fresh diesel and still have no high pressure fuel out of pump to rail. Checked continuity from ECM to fuel solenoid on top of pump and loaded tested circuit with flood light no issues. I can't get my ET to hook up due to a broken pin on data link connector. I see no faults on screen. Only thing I see is no RPM on data screen when cranking. Could a bad crank sensor cause ECM to not send signal to solenoid to fuel or internal issue in pump? I've tried to jump solenoid but iam unsure if it needs power/ground to open or power/ground to close the solenoid and I can't find anything on SIS on how to jump it. It's stuck In a pit 20 feet down so it's quite the problem. Any ideas? Cat wants to sell cab harness for this missing/broken pin issue on data link. I've only got customer units in the shop so I can't go hacking their harness up to steal the data link connector, unless there is a super secret data link connector for the ECM in the engine bay I can't find it?
Machine#CAT0321DANAS00453 Engine#gdc29127
Had bad crank sensor on 314DLCR (SSZ) same engine minus 2 cylinders. Didn't show RPM when cranking, and,, obviously, wouldn't start. Book makes it sound as if Cam sensor should still allow running. Book is wrong.
As for diagnostic connector, just crimp on a replacement pin. It ain't rocket science, but...you need an extraction plasti-tool to remove old pin, and crimper for new pin.
Yes we have tried extensively to get some sort.of pin inserted no luck. Do you know off hand if the ECM pulses the solenoid on the pump? Or just straight up power/ground like an old school fuel shut of solenoid?
Personally I’d replace the crank sensor before fighting w the pin replacement..
Crank or speed sensor? Seems to have 2 in bell housing right beside each other. One looks adjustable the other bolts in
EXCELLENT info.!!! Thanks HM.
Excellent thank you. If it comes down to the pump ,Do you happen to know the torque on the pump gear nut. The timing procedure looks pretty basic, line up the #3 and lock the pump?
Ok quick update, bypassed the wiring to the fuel solenoid and we now have fuel coming out on the high pressure pump. But still won't start???? Something must be telling the ECM to not fire the injectors.....hmmm
Would you like an electrical schematic.? I can send you one if it will help.
That'd be great. What iam not understanding is I have CAT ET but it won't connect. But at the shop I can connect to a kenworth with a C15 cat. The pin on this excavator was missing and I cut a used data link connector out of a old harness and hardwired it back but but still won't talk? I know the ECM is turning on as I have my reference voltage to all engine sensors key on engine off, Will it not talk because it's a 12 volt system VS a 24? We use a nexik USB 2.0
12v or 24v should make no difference AFAIK. I have run an ET Comm adapter off a 12v motorcycle battery before now to get power to look into an ECM. Regarding the NEXIK, no idea. Keep an eye on your message. A schematic will be with you directly.
Have you been able to connect to any Cat off road equipment with your nexik before? Cat off road use CDL (Cat Data Link) which I believe aftermarket scan tools have trouble with.
Yes I have. Mostly gensets and aggregate equipment for a local gravel Company.. but all that stuff is always 12 volts because it's on the smaller side of things
Good point. On-highway and industrial engines generally tend to use J1939 as a Data Link. It's usually only machines that use CDL.
What is this CDL? Yes most stuff we hook up is j1939 & j1708. What is the CDL data protocol? Is there a jumper we can purchase or do we need the actual CAT one? Tons of equipment around and work around, Iam a firm believer in suck, squeeze, bang, blow & power, ground and ignition voltage and you can fix almost anything with enough access to information and an open mind
CDL stands for Cat Data Link. It's Cat's method of communicating between ECMs and also with an external diagnostic tool. I have no idea what the protocol is, but someone here might know.
Will try this 12 volt motorcycle theory as when I tested the data link connector it has all the proper voltages and resistance on the data lines just no communication
We often used an external battery in the office as a way of powering up an ECM and the Comm Adapter. To get an ECM to communicate requires very little amperage. For engine ECMs they only use lots of juice when the fuel injection side of the ECM is firing the solenoids on the fuel injectors. Below is what the wiring needs to look like for a Cat Comm Adapter. What's on the right is the 9-pin round Deutsch connector that plugs into the Cat Comm Adapter. On the 2-pin breakout harness the Batt+ goes to Pin A, the Batt- goes to Pin B. If you want to connect to an ECM when it is off the machine then you will also have to supply Batt+ to all the Pins (there may be more than one) that require key switch power to light up the ECM. Looking at that 2nd schematic I sent you there are 4 x Batt+, 4 x Batt-, and 1 key switched power.
Without getting too far out into the weeds, here's a few notes on CDL The CDL + & - lines basically switch between ~ +1 and +4 volts mirroring each other to produce the signal. Compare to CANbus which starts with both lines at ~ +2.5V and then sends one line high and one low. CDL is slower than CAN but more robust and less prone to interference. CDL doesn't use terminating resistors so checking resistance between the lines doesn't work, unlike CAN. The only real test you can do with a multimeter is to check the voltage between the + & - lines. It should fluctuate between about +1 and +4V. If your scan tool doesn't explicitly state that it will work with CDL, assume that it won't.