Why won't this VIN Write????
08 Dodge Sprinter 3.0 diesel No crank new ECM
I first got this call to program an ECM on this Sprinter which happened to be owned by one of our local Snap On dealers. It had a new PCM from the dealer. The PCM had been replaced because of a no start condition. I performed the programming and had no issues until I got to the VIN write procedure. On this vehicle the VIN must be written in order for it to crank which must be done with the Micropod II or capable scan tool. Under the misc. functions in WiTech II there are two options for VIN rewrite (the Mercedes/Chrysler software is strange) when you click on one option the tool says that it is unsupported. The other VIN rewrite option gives me an error code. process.filestackapi.com/resize=h:1000… process.filestackapi.com/resize=h:1000… The old ECM had no communication and smelled burnt So I was under the impression that I was battling a failing replacement PCM or a scan tool/software issue.
I also had 4 codes in the new module. process.filestackapi.com/resize=h:1000… 2100 Electric fuel pump (fuel level sensor) 2199 Measure unit (Fuel quantity control for high pressure pump) 2502 Fuel pressure regulating valve (boost pressure regulator short to ground) 3069 undefined Notice that the DTC description for the 2502 code reads “fuel pressure regulating valve” however the service information describes a fault in the boost pressure regulator. process.filestackapi.com/resize=h:1000… The code 2100 which is shown as “electric fuel pump” is really a code for the fuel level sensor. process.filestackapi.com/resize=h:1000… I guess prior to owning any OEM scan tools I imagined how nice it would be to have OEM tools and service info where everything is correct but in this case I might as well have been reading a poorly translated Chinese takeout menu. I assume this is because the information is taken from Mercedes and adapted to be used on the WiTech platform and is probably the reason why there are two vin rewrite procedures.
I also noticed the radio had no communication and would turn on and off randomly as well. I told them that whatever had likely caused the old ECM to fail is likely related to these codes, billed them for the programming, and told them if they needed help with the diagnostic to schedule some time and took off for my next call.
About a month later I get the call that they have been through everything on this truck and cannot figure it out. Although I’m dreading working on this Dodge/Mercedes I head out there to take a look at it. It had the same symptom, will not let me program vin, no crank and same 4 codes. process.filestackapi.com/resize=h:1000…
I really didn’t have much of a direction so I started by reading into the codes one by one. There is no description whatsoever in Techauthority for the 3069 code and the boost pressure regulator seemed like the easiest code to begin diagnosing. I did a quick check of the power supplied from the ASD and ground circuits which were both good. process.filestackapi.com/resize=h:1000… The signal circuit did not have any continuity to ground and when unplugged and the same code would set. Searching for a list of potential codes I found code 2500 which is a circuit open code. process.filestackapi.com/resize=h:1000… My assumption is that the circuit open code should set if the regulator was unplugged and since I had verified the wiring was not shorted to ground.
I was thinking the issue was likely internal to the PCM. I researched powers and grounds for the module. process.filestackapi.com/resize=h:1000… I typically do my powers and grounds checks with a sealed beam headlight. If the circuits can handle enough power to brightly illuminate a sealed beam than they should be able to power a module. For the purpose of this case study I used a test light. With key on should have healthy power at pins 1, 5, and 7, as well as healthy ground at pins 2, 4, and 6. I found power at 5 and 7 but no power at the black/grey wire on pin 1 of the ECM. process.filestackapi.com/resize=h:1000… That power comes from fuse 16 which I found missing from under dash relay block causing missing power. process.filestackapi.com/resize=h:1000… When the fuse is replaced all ECM codes clear and do not return. I attempted to rewrite vin number multiple times but still received an error and could not get vehicle to start. process.filestackapi.com/resize=h:1000… I assumed we had likely caused damage to the replacement PCM when attempting to program it with one missing power. Since the shop had purchased the module from the dealership they decided to tow it there to see if they would warranty the unit. Once a new PCM was installed and programmed the vehicle started and ran great with no codes returning. process.filestackapi.com/resize=h:1000…
Since then I have found a module reset procedure within the guided diagnostics in WiTech II. I have used this function to recover modules that have had programing failures and I wonder if it would have allowed me to fix this Sprinter without replacing then PCM. The interesting thing about this is that the module had consistent communication with one power missing and I was able to program it and look at the data stream without any issues. I would have never expected this bizarre concern to be caused by a missing power and was really only led to that conclusion because I never recommend replacing a module without checking powers and grounds.
On the VIN write error message, I noticed that the reported battery voltage was 10.64v and didn’t see the battery voltage in the successful write screen. Was the system voltage >12.6v when this was being reported?
Scott, This trucks battery was pretty bad. This case study was an afterthought so all the data was collected after I had taken the programming power supply off but it was originally done with good voltage. I never did get to successfully write the VIN as even after the missing power was restored it still gave me error. The final fix was the dealer replacing the PCM under warranty. Essentially the shop towed it to the dealer claiming that there was something wrong with the new PCM. My thought is that we had an issue programming the PCM with a missing power but it did not fail, freeze up or have any of the typical symptoms of a failed programming.
That is a MB VIN, I would try a MB Xentry. We have no trouble programing Sprinter/Dodge/Freightliner with Xentry.
Hey Mike, great writeup and good story. Working on these Sprinters, especially their electrical issues, can be very frustrating. There is a little more information (and more accurate information) in the Mercedes service info, so I wouldn't give up on OEM tooling just yet. These Chrysler/Daimler half breeds are a mess, the crossfire is pretty bad.
Your 3069 code is garbage. It doesn't exist in SI, or in any quicktest I've stored for these vehicles. The other codes are for the fuel pump, pressure regulating valve, and quantity valve. The fuel pump relay control circuit is powered by fuse 16 (as well as the starter relay control). So no fuel pump activation and no starter activation. The PRV and QCV most likely are powered by the CDI module via the power that comes from the fuse.
As far as the failure to program the VIN there is a small chance that it would have worked with the Euro version of the VIN, the FIN.
The FIN uses a six digit designation for the vehicle that is sort of compressed to four alphanumeric characters in the VIN.
There's no documentation on the function of that power input to the CDI module so it's hard to say if it affected the VIN write. It's a possibility that low voltage interfered with the communication of the scantool to the CDI module as Scott mentioned, if that was the case at the time. Most likely you had one shot to get it right and after that it locked.
As far as the root cause, I imagine the CDI module shorted out due to an internal fault. The PCV and QCV or relay wiring are unlikely to be the culprit. There aren't any other consumers for F16 as far as I can see.
The guys that worked on this before you kind of set you up for failure. That fuse didn't just evaporate, someone removed it and didn't tell you - thanks! It's very easy to get off on the wrong foot when you go to program something for someone and the vehicle hasn't been diagnosed and repaired correctly.
That fuse panel is mounted pretty low and uncovered right near the drivers footwell. While I'll admit most of what I'm told by techs during diag calls is a lie I am pretty sure the extent of their diag was finding no comm, sniffing the PCM and replacing it so I don't suspect their techs removed the fuse. I was thinking that maybe the fuse got knocked out which had caused the original failure. The more I think about it I wouldn't be surprised to find out that the module failed and the Snap On man was fooling around with fuses which just compounded the problem.
Where do I learn about this FIN and is that possibly why there are two VIN write options under misc functions? Coincidentally I have the Autologic NTCS flyer on my desk but I have a scheduling conflict and will not be able to attend. I would really like to devote some time to Euro training as I'm not yet ready to call a PCM a CDI!
I'm religious with the programming power supply. One of mine is actually hard mounted in the truck with 25 ft of cable and is powered by an inverter and some Hawker batteries just in case I need to program a car in the desert! I'm pretty sure the WiTech software will not allow you to program without correct voltage (I haven't given up on OE tooling and love the WiTech... at least when I'm working on Chryslers). Essentially I had no voltage whatsoever on one circuit but the flash never gave any errors. You mentioned that there is no documentation on the function of that power input. Is that type of info available possibly in Mercedes info on some vehicles? I know that information must exist somewhere and I wouldn't be surprised if some engineer somewhere could take that 3069 code and relate it to that specific circuit but I wouldn't know where to find it even if I could.
I wish this was one that I could show a logical diagnostic process but there really wasn't. Other than reinforce the importance of checking power and grounds I thought it might make a good conversation. I appreciate your feedback!
The issue you're having with the VIN write is caused by the fact that witech II is only designed to work with 2010 and newer Dodge/Chrysler vehicles. To write the VIN in the '08 Sprinter, since it's a CAN bus dodge vehicle older then '09, is a physical witech or other capable scan tool. Chrysler doesn't support this function in their j2534 legacy application for '09 and older chrysler vehicles since they only technically support the reflashing of the original ecm/pcm/tcm up until the 2010 model year, which is when you could then use the witech 2.0 software. I hope this helps.
I thought everything on Witech 1 was transferred into witech 2? I thought the witech is still even available and the old units do not work on the new software correct?
No, witech 2 is only backward compatible to the 2010 model year. Not anything '09 and older. What do you mean when you say the old units do not work on the new software?
You mean it's only backwards compatible on Sprinters only. I use witech2 on older vehicles daily. Unless I am missing something.
I've never owned the original micropod but I thought I was told it's discontinued and not longer supported?
What tool are you saying I should have used?
Are you sure you're not using witech 1.0 on the vehicles older then 2010? They look alot alike..
The photos above show Witech2.
Witech 1.0 was used with the first generation of Micropod and is discontinued correct?