rbebenek

Hello, new to the Forum, name is Rafal.
i started at a company that has a sprinter stuck in limp mode. Been trying to diagnose it using the star/xentry system that they have (off ebay) and unfortunately i am quite stuck here. The closest mercedes dealership that looks at sprinters is 200 miles away so unless i have to drive it down there, i am avoiding it. So onto the problems. I am in Northern Michigan BTW.

Back in December, it died on us on a delivery route, and had to be owed, the random mechanic (not MB) diagnosed as alternator and replaced it. Fine for a day, went back to shop on a tow truck. Then their answer was diesel is gelling up (around -10 for a week or more). So added additive but have still had random problems.

The last week, this happened twice at random times and have no idea what is causing it. The dash turns off, everything turns off, vehicle starts to sputter and dies. I get a battery charger turn ignition on and everything lights up as normal, plug in the xentry and all the cluster control units, adblue, scr, scm and others show as under-voltage. Xentry is also beeping at this point and telling me battery is 10.9V. Battery is about a month old, same rating as original one. So i leave it off for about 10-15 minutes and then it starts on its own, both times. Have not had to do or more anything, just starts after letting it freak out for a while. However, i would really like to figure out what could cause it to be so sporadic, and dire. Also, if it is a short, i cannot imagine that it would disappear so quickly, without doing anything and then come back when it feels like it. So any ideas on the electrical, what to look for, what to check in xentry would be amazing, since i am stuck... One odd code is the PTC heater booster saying over temperature, but not sure if that is just an odd code due to under-voltage or an actual problem. I do get an error with the alternator in the LIN bus on the under-volatege but not sure if that is the cause or the after math of the drop in voltage. 109B00 (Component N3/30 received no LIN message from component G2/7), 109A00 (Component G2/7 Alternator with LIN bus has a malfunction. The alternator codes only show up during the under-voltage issue when dash turns off and the sprinter sputters to a stop.

Also, from what the owner said, the sprinter has been stuck in Limp mode for almost 2 years now. The limp mode sucks but since it is driveable, they have basically been ignoring it, since dealership is so far away. So it has a power band between 2000-3000 rpms. anything below 2000 it slows down instead of speeding up. It also refuses to go above 3000 rpms. Even going down hill, if i shift down and it pushes it over 3000 rpms, the engine will cause it to brake and slow down to get below 3000 rpms. That is a bit annoying since even onthe highway keeping it above 70 is a challenge. My question on the limp mode is, would te DPF being at like 270% according to xentry cause it to stay in limp mode? These are the codes under CDI6 in xentry. 11A700 (DPF soot content too high for regeneration, tried and it did nothing, took me 2 hours with the limp mode to keep temp high enough), 12BC00 (Component B28/20 has plausibility error), 118900 (Component B60/4 Exhaust back pressure sensor has a plausibility error).

If i clear all codes, then it always comes back with the CDI6 error codes for 2 components and the DPF being over capacity.

Any advice (besides driving it off a cliff will be super helpful , this thing is a giant PIA and i am hoping to keep it running a while longer).
Thank you!

kajtek1

When there is limp mode, it has to be a code. What is it?
Battery low voltage is self-explanatory. You have to check what is costing that.

rbebenek

When i run the quick test, the only codes that are constant are on the CDI6, DPF being full and 2 sensors mentioned above. Get some other random ones (1 of the brake sensors is busted, the spare tire is missing so tpms throws an error, and a few of the interior lights are missing, and external arent working so those are there always as fault codes). However i do not worry about those as i dont think an open circuit in a lamp would cause it to have issues with no power. I call it limp mode since that is what is seems like. I dont see a single code in any part of xentry that says limp mode though. When i get the van back tomorrow afternoon can look through xentry again to see. If there is a specific module i should be looking at, that would be helpful. This is a very learn as i go endeavor

Basically the engine has no power. Leaving it in D, makes it difficult to pick up speed as it tends to shift at or around 2k and drops the RPMs below 2k where we lose all torque/power. The turbo does not seem to be engaging at all. Why i call it limp mode, but cannot find any errors pertaining to it. It might be something else, just not sure what to call it?
Thanks!

kajtek1

Clog DPF sure will stop the engine from performing.
Can you force regeneration with your scanner?

kajtek1

BTW isn't Michigan having only B20 available? I hear lot of feedback that common rail MB don't like the mix.

rbebenek

I tried to do the regen, because i cant really get power outside of 2-3k RPM range, it took me over an hour of highway driving to keep temperature constant enough to have the scanner "complete" a regen. However it did not work (tried twice). Now the error is that the DPF soot content is too high for a regen. So i have to replace it i would guess? i found them on ebay for 400-600$ for a new filter, so not that bad compared to the MB price of 6k i was quoted. As long as it works i don't care if its from ebay and they guarantee them to work. So in theory if i replace the DPF, and clean the sensors (or replace if they are broken), it should potentially give me my power back? Once the DPF error goes away?

The diesel, yes a lot have moved to B20 in michigan, but we still have stations that do B5 and we try and only fill up at those. So that shouldnt be the problem. i assume.

kajtek1

I bought those above for my E but haven't used them yet.
You will find video on youtube how guy used them on Sprinter and lot of guys confirmed good results.
But you better have computer-generated regeneration than driving in unknown.

steeven001

For your powerloss and under voltage issues get under the van there is a y cable for power that comes from the battery to starter to alternator it also has a 300amp fuse in it. Check if this cable is corroded or melted. When this cable goes bad it can give you all kinds of random codes because of the dropping battery voltage. The cable is easy to see it runs across the back of the oil pan.

Maybe your old alternator was fine and the mechanic misdiagnosed it because of this cable.

I've seen this issue many times where I live (Toronto, Ontario) because of the all the salt we use on our roads in the winter months.

Also there is another forum called sprinter source where you might be able to get much more help than here.

rbebenek

Thank you kajtek1 i will definitely look at the dpf cleaners, and try those first, never heard of them. much cheaper to try that first before replacing i guess. I am assuming i would still have to pull the dpf out and clean it out? i know probably stupid question but again, i am learning

Steeven001, i tend to agree with the misdiagnosis, because even now been sitting in the sprinter for the past 3 hours, running it with heat on max, lights on, and of and whatever combination. When i got in the sprinter this morning and started it, the battery already showed 11.4V, and after about an hour of running it dipped down to 10.7V. Xentry at that point beeps continuously and warns of the under-voltage. Under the alternator section it still shows as its putting out 14.5V but how accurate that is, i am not sure. After 3 hours, i turned all extra things off, so it was just running, no lights, no heater, no radio. the battery would get to a maximum of 11.2V. but never higher. So i turned ignition off, waited till dash turned off and then started it back up, now showing 12.9-13.1V nonstop and constant, with everything on (lights, heater, radio). So i am leaving it running for a while, to see if it drops down again. That was 15 minutes ago, so i will report once i let it run for a while. In the meantime i am going to roll around under it and find that cable and see if anything is melted or corroded. Looking at the top side of the alternator the one cable that comes off it, is already green, from corrosion i assume? The alternator was replaced in December with a 252 amp version, date on the label says 10/2017. Unless they used a re-manufactured one and we got a dud? i am hoping its the cable. i do not really have any way to test the alternator, unless someone has a trick up their sleeve

Will post back what i find, if i can take some pics, maybe one of you can tell much quicker with those

mbdiesel12

Perhaps you could try this simple test to see if your gauges are reflecting accurate voltage. First, let the vehicle sit for maybe 30 minutes to make sure it has gone into "sleep mode" and no power is being consumed.
Make sure you do not have any lights or accessories on inside or outside the vehicle. If you have a multi-meter, place it on the dc voltage setting and check the batter voltage. A normally charged battery should be around 12.6v or so. Anything above about 12.2 should be OK for this test. Now start the car and do the same voltage check on the battery. You should see a charge rate around 14.2 or so.

This will tell you if the charging system is putting voltage back into the battery without depending on the vehicles gauges. A bad battery cable is a possibility as well as a bad ground. Another future step would be to check for a "power off battery drain".

rbebenek

On the Y cable, only ones i have found are specific to an 180AMP alternator, if the mechanic put a non standard one of 252amps (what the label says), then will the replacement cable be able to handle the higher amp output?
http://europarts-sd.com/item.asp?cID=109&PID=2398
For example.

rbebenek

Will go test now, have multi-meter with me. Thanks!

rbebenek

Tested the battery when everything was off, was showing around 12.6V with it sitting for 30 minutes or so. Started it, the voltage dropped to 10.5 then went up to around 12.4 and sat there. Then started to slowly drop as time went on. Turned it off, waited till dash turned of, started again, same thing, 12.6 down to 10.5 then up to 12.4 on the battery before slowly creeping down. Third time of shutting off, and restarting without even waiting to everything go to sleep mode, and battery started around 12.5V dipped to 11, then up to 13.7-13.8V constant and was climbing slowly, but not much. 4th start same thing, 12.4V to 11V up to 13.8V when running. I will test again later this afternoon to see if it keeps doing the same thing. So if it is showing 13.8 once running, it is charging the battery and i should have no issues, i assume, if i left it running long enough at the the voltage that is not really charging, then it would have eventually sputtered to a stop with under-voltage reading in every control unit in the computer.

While it was running, i rolled around under it and traced the Y cable from alternator to starter and behind the oil pan, there is a lot of missing/cracked insulation. At this point is it same to assume that the cable needs to be changed out? Since that seems to be culprit with the randomness of charging due to resistance on the cable? My question above still stands though, can i use the MB cable on the link i put up above with the 252 amp alternator? even though cable is rated for 180 amp alternator? or is there a different cable i should be looking at? OR can i just make my own and test it for now? Thank you all, this has really been far more helpful than any mechanic i talked to or even when i call MB. you guys are all awesome!

mbdiesel12

To me it looks like the charging system is behaving normally. Dropping to 10.5v or 11v is what you should expect with the starter load being applied. I'm not an expert but I believe that MB has a two stage charging system like our Acura. See that little black box on the positive battery terminal? My guess is that's the two stage charging module. If it is, it monitors the battery and sends signals to the ecu on how/when to charge the battery (IE- low charge mode and high charge mode). It's not like the old days. Two stage charging systems can make things look like the charging system is acting funny when things are actually normal and being monitored/controlled by the charging algorithm.

The algorithm takes into account many things like battery temp, load, etc. to determine when to charge and how much to charge the battery.

At this point I'm not sure what problem you're still having. Is your battery going dead and the car not starting or are you just concerned about the randomness of the charging system?

I don't want to to go off on a tangent but here's a tech article about dual mode charging systems and how they behave. http://opensiuc.lib.siu.edu/cgi/view...text=auto_pres

Hope I'm not confusing your issue.

kajtek1

Testing charging system with glow plugs is whole science as not only GP take big current, but they are coming on and off for some time on cold engine.
That is why you should test charging once the engine is warmed-up and 13.8V looks good, but do the load test aka turning all headlights and blowers on.
DPF purge is done via sensor hole, so no DPF removal necessary. LM is selling special sprayer for a fortune, but youtube shows how owners converted cheap garden sprayer for the job.

mbdiesel12

I'll add my opinion for whatever value it has:
1. Sounds like you may have multiple, perhaps unrelated problems going on. Diagnose them separately. IE- electrical vs limp home mode.
2. A blocked DPF could and probably will result in limp home mode. If limp home mode is shutting down a running engine maybe that's the cause of the low voltage problem and the lights coming on as the engine
cuts out.
3. You replaced an alternator and the new one looks like it's working. Since you didn't test the old one the same way, maybe it was working also.
You haven't said the battery is going dead on you so the charging system seems OK. Your 12.6V reading proved that unless you recently charged it.
4. If your battery is not holding a charge do a key off battery drain test to see how many mV you're losing. A huge loss could point you to a major component like a starter/battery cable.
Anything more than around 100mv is probably indicative of a battery drain if sleep mode is over.
5. I have no way of knowing what your codes are telling you since I don't have a manual. So all the above is just a guess.
6. Last, regarding your battery cable, it's not a good idea to undersize a cable. If the alternator is capable of 252A you could melt one rated at 180A. Not worth the risk IMHO.
Keep us posted.

rbebenek

Update Time!
Ok so been messing around with it the last few days. The cable might have some influence on it, but this morning this happened. Before i started the sprinter, checked the battery and it was at about 12.6v. Started it, the battery fluctuated down to 10.5 then settles at 12.4V. Checked on battery terminals and before the black box in battery compartment, both showed 12.4V. Waited about 30 minutes and it was down to 11V on both battery and on line before the black box. So i can eliminate the black box a the issue since voltages are same before and after it. As it kept dropping i got under the sprinter and put multi-meter on the alternator (took me about 15 minutes) since balancing flashlight, meter and 2 probes (cant find my aligator clips), took me a while. Once i tested it, the alternator showed up anywhere from 9-8.4V as it fluctuated at the lead coming right off the top of the alternator. So i said crap in my head, went and checked battery and it was showing same voltage on terminals on battery and before the black box. At the same time i looked at the dash and parking break, traction control ,etc were all illuminated, due to under-voltage. So i killed the engine, left meter on terminals and watched the battery go from 9.5V to 12.5V in about 4-5 minutes. Once it got above 12V i started it, the dash lights all turned off, and it ran fine. Now the voltage on the terminals, and line before black box was a steady 13.4V and has been holding.

It usually is like that, if it starts up and is sitting at 13.4V right after starting i wont have issues all day, if i start it and its below 13V it will creep down to 10V over 30 mins or so and then the under-voltage will make it choke on itself after some time...

Can i assume at this point that the alternator that was put on in December, by a random mechanic (again had no influence on whom did it or what they put on, as i was on vacation in europe when it died on the road), is a dud? or is there something else i should test prior to this. I never have to move anything or change anything. A simple turn key off, wait till battery settles above 12V again, then start back up is usually enough to get it to "fix" itself albeit it till the next restart. Can anyone explain how an alternator can spin, but put out such little voltage? This morning when i started it up, i noticed a squeak coming from alternator, at least it seems like it is coming from it when i am under the vehicle. On the 2nd start the squeak is gone. Any advice is always greatly appreciated

mbdiesel to answer your questions.
1. "Limp" mode i am ignoring till i can get the electrical sorted out, liimp has existed for over a year and its fine to drive once running.
2. I will clean dpf with the kit mentioned above in the post once i fix electrical.
3. the old alternator had no idea, was 6000 miles away when this issue started, and couldnt tell you exact symptoms since it was towed to the nearest mechanic and they diagnosed it somehow.
4. Battery has never drained down to noting, or not enough to start it again. Even if it sputters to a stop. if i wait 10-15 minutes, the battery voltage will climb back up on its own to 12.5-12.6V and then it will start it again no problems.
5. the codes are very limited even with xentry, because the main ones show DPF regen cant be done, etc. The others are usually related to multiple components turning off due to under voltage. Noting specific just under voltage shutoff across the components.
6. cable i agree, if the alt is bad, then i will get one rated for that vehicle, and not go over so i can replace that cable as well, at the same time.

mbdiesel12

I think you're on to something here. It almost sounds like an intermittent short in the alternator. Maybe when it heats up. Also, I wonder if there could be a short in the starter circuit that's drawing current. Have you checked your starter cables and ground connections.

Maybe somebody else can chime in here.

kajtek1

That's clear indication of charging problem.

rbebenek

yay now get to argue with a mechanic who is 90 miles away about something he put in 1.5 months ago and it cost us 1200$ for part and labor :/
ill keep you all posted on developments also i will talk to a mechanic down the road who has done work for me for years..

mbdiesel12

If it's that new it should still be under warranty. Hope you saved the receipts.... call first to make sure they'll honor the warranty if you bring it in.

rbebenek

yea my boss is looking for the receipt. so we will see if he finds it
if not, it sure will be an expensive lesson for him to keep paperwork around... instead of throwing it away.

mbdiesel12

Even if you don't find the receipt I'd call the shop anyway and explain the symptoms. If they're an honest shop they should have a record of the repair and at least take a look at the problem to verify the alternator is or is not the problem. That's the least you can expect for $1200...

kajtek1

Bare in mind that low voltage can be result of bad connection, or even short in the system.
Before you go with new alternator complain, I would compare voltage close to the alternator with battery voltage. Check all the connections and even when they look good, disconnect them, spray with cleaner and connect back.