jrramage

We have a 2005 E320 CDI with almost 120k on it. Several times late this summer it left my wife stranded. Three times on hot days she shut the car off returned a short time later and it wouldn't crank. Once the car cooled off it would restart with no indication there was ever a problem. Last week it did it again and it hasn't cranked since.

It has acted the same every time. All the dash lights light up...ESP malfunction is displayed...everything works electrically...no crank...no click...nadda. One of the times it did this I tried to scan it for codes and it had a connection error. I switched a few relays... no change.

I have found a few cases of this in various forums but the only one that posted that it had been fixed, didn't really know which module caused the problem. The battery module and "some other module" were replaced and the car was fixed. There are other cases of this with the cooling fan blowing full bore when the car is keyed on. In those cases it seems it is the ECM.

How do I go about testing this? Even better, does someone know what causes this? Thanks, JR

theunderlord

my money is on the crank position sensor. not 100% sure because of the CDI version, but a ton of the CPS's have been going bad lately.

the "wont turn over when hot" symptom is how i'm diagnosing this.

Diesel Benz

I understood that it does not crank, meaning the starter motor does not even turn the engine (there would need to be more than a click and now there was not click). CPS would not prevent the engine from cranking.

Did the key turn in the ignition slot? Are you sure the battery was not flat?

Plutoe

The things you can check are the K40 and battery voltage. The things you can't check is rail pressure----if low will not start---However very surprised that ther are no CEL's. The best way is to get a scan. Good Luck!!

jrramage

I agree...I believe the engine would still crank if the CPS was bad. (turn over, rotate, etc...ever start a Model A or other old car with a hand crank?... where we got the term: crank) If it is a CPS issue the engine cranks but either has no tachometer, won't fire, won't run, or runs terrible depending on what systems use the signal. (I have encountered a couple of these.) The CPS is useless before the crankshaft turns, am I correct?

The starter doesn't engage nor does the solenoid click. Key turns...battery is perfect. My wife drove it to our place of business and shut it off (it was not hot outside this last time)...I pulled it in our shop about 5 minutes later without incident...tried to move it onto the lift less then a minute later...no crank...died just in front of the lift!

jrramage

Plutoe, what is the K40. Rail pressure will be low if the engine (high pressure diesel pump) is not turning, correct? Are you referring to pressure from a lift pump? Thanks, JR

Plutoe

My K40 is under hood in the passenger side control module box. I would go to EPC to confirm your location.

Rail pressure sensors are on the ends of the fuel rail, the rail(after pump) that your individual injectors are piped to.

Depending on the CDI level on your car that rail, rail pressure is very high and if the actual values do not meet the preset(ECU) values the car will not start.

An afterthought, have you run the car with the second set of keys, I know the key batteries have nothing to do to the DAS, but if the recognition signals are absent, the car will not be recognized and will not start.

I would also go to EPC and review the starting circuit there is a whole lot of of control modules---key switch, front SAM, gear recognition switch bla bla.

That is why if you have a copy of DAS Xentry you will pin point the issue promptly. If not ------------------

jrramage

Does the car need fuel pressure for the starter to engage? I have a couple of sprinter vans and know that the starter will turn the engine when the fuel filter is empty and will fill as you crank.

Plutoe

That is a good point, I believe the answer no---the car will continue to crank, but the DAS will not be satisfied and therefore will not start. Therefore fuel rail pressure is not an issue because you can not crank!!
Which supports the issue is with the DAS.

However your fuel filter analogy does not apply.The fuel rail does not empty.

jrramage

What is the DAS? Is it a module? How is it tested?

I have had several commonrail vehicles start and die after fuel filter change if the filter isn't full enough on restart. After more cranking or priming it will fill the filter, pressurize the rail and start again. The vehicle dies because there is insufficient fuel pressure in the rail caused by low fuel (and air) in the filter...right? The same happens when you run out of fuel on the road. The vehicle will crank but will not start until the rail is pressurized again. The presence of fuel in the rail is not adequate...the injectors cannot "pull" the fuel, they are simply a computer controlled electomagnetic valve releasing a calibrated amount of pressurized fuel.

jrramage

Tried second key this afternoon...no change. What is DAS Xentry? Not familiar with the DAS system at all. I will be researching it tonight...

TMAllison

DAS = Drive Authorization System. Security between key and ignition.

DAS Xentry = diagnostic software.

SDS = MB's diagnostic software.

Because the car wont crank it doesnt seem like a CPS problem to me. Possibly key/ignition/recognition related problem.

When it doesnt crank, does the steering wheel lock retract when the key is inserted in the ignition?

Could be the NSS. Next time it wont crank, try shifting to N and see if it cranks then.

jrramage

I have tried starting from the neutral position...no difference. I believe the steering wheel unlocks as well but I will check tomorrow. Everything works when you turn the key on, it just won't crank. Something else...the temperature icon on the dash turns red when the key is turned to the on position and one of the triangle dummy lights as well. The lights acted like this the other times as well. I noticed that when I went to restart if those lights were normal when I turned the key to the on position the ESP malfunction message would be gone and the car would crank and start perfectly with no malfuntion message. I will post a picture of the cluster tomorrow.

jrramage

Actually I remember now, the steering does in fact unlock when the key is turned on. One of the times it acted up we had to push it out of the way in our friends' driveway.

jrramage

photo of cluster...

jrramage

Any further thoughts??? Are we at a dead end without Star diagnostics and Xentry?

jrramage

ttt

ctravis595

no fix? i'm having similar issues with my 02 w215, sometimes it will start but a lot of the time it won't even crank. the key turns and the engine doesn't so i know it's not the CPS, i even swapped out the CPS

jrramage

Not fixed yet. Replaced front SAM...didn't help. Still working on it when I can...she really wants her car back

Plutoe

Well its been eight months now, I guess she can wait another year or more until you spring for a DAS Xentry quick test and really excite her!! Tow the car to Tampa, I'll test the car for nothing!!

jrramage

Plutoe, I purchased everything from Shardul...with CAN bus issues it seems you are limited to what you can diagnose because the system shows it is disconnected. I have been going thru wiring diagrams to figure out where the front SAM gets the signal to power the ECM. Thoughts?

Plutoe

I think I know what you are trying to do, except most diagnostic equipment vary widely in their capabilities bla bla bla.

Think of the CAN simply as a closed H and L communication system and all the sensors and control modules are interconnected within their respective communication system.

Your scanner is crap and can't diagnose squat except telling you that it is disconnected, it is only disconnected when the battery is disconnected. With my DAS Xentry the battery MUST be on and or car at idle, if not in wifi road mode,therefore the CAN bus is never disconnected, sensors and or control modules may not be communicating in or out because of faults or because you disconnected a module from the CAN, like when you change out a window regulator, you have to remove the regulator connector, that produces a fault even when reconnected and then has to be cleared.

Get back to basics, screw the wiring diagrams and wasting your time and money on SAM's bla bla-------have a proper scan done on the car. Learn the real problem!!

ctravis595

plutoe, how deep in tampa are you? i'm over in tarpon springs and it'd be awesome to sort this issue out without having to bend over at the dealer

if it's not a bad sam, then i think something like the brake light switch, the esp module, or a bad ignition switch could cause the engine not to crank

Plutoe

Ah the Greek festival, great food and folks over there.

The small shop is in Apollo Beach 33572, however I do much used car dealer mobil work all over central Florida---- DAS Xentry goes anywhere as long as the car has a good battery(12v+)

We go over that way for lunch on the weekends---not regularly 4105962488

jrramage

Plutoe, what am I missing? I bought a t30 IBM with DAS Xentry and all the other software that comes with it and a MB multiplexer. I have ran the scan but got very little useful information... I am all ears.