Check Engine Light ML320 CDI
12-27-2007, 10:31 PM
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Check Engine Light ML320 CDI
Check engine light came on at 16500 miles when temps droped below 20F. Vehicle went into limp home mode, and would not rev past 2500. Dealer diagnostics showed codes "2078-B28/8" open voltage supply at pin 30 on ECU, and claimed the fuel pressure was too high. Dealer flashed the ECU per a TSB, and replaced the fuel pressure differential sensor. Bought vehicle new, and this is the first time I ever had any issue. Also first time temperatures had dropped that low. Have to wait until temps drop again, probably next week to see if fix worked. Has anyone else had this problem or heard of it? Thanks.
12-28-2007, 06:26 AM
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12-28-2007, 07:20 AM
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C350
Check engine light came on at 16500 miles when temps droped below 20F. Vehicle went into limp home mode, and would not rev past 2500. Dealer diagnostics showed codes "2078-B28/8" open voltage supply at pin 30 on ECU, and claimed the fuel pressure was too high. Dealer flashed the ECU per a TSB, and replaced the fuel pressure differential sensor. Bought vehicle new, and this is the first time I ever had any issue. Also first time temperatures had dropped that low. Have to wait until temps drop again, probably next week to see if fix worked. Has anyone else had this problem or heard of it? Thanks.
http://www.benzworld.org/forums/w164...ine-light.html
01-01-2008, 12:50 PM
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So far so good. Pressure sensor part went in and no issues so far. Still waiting for temps to go down more again to be sure. So far only down to 25F and runs great. This week will tell. I saw thread by XJ9. Will also post this to the other member as they seem to be having similar issues. Thanks for helping. Will update as temps drop more.
01-04-2008, 01:19 PM
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ML320CDI 2007
I had the same Issue back on Nov 28th, and it took 4 weeks to get the part and replace it, stating the first time it was a "random meaningless error" - they later said it was the voltage I had was "too low"... The dealer reset the error code the first time, and told me it was fine now, and after driving it 15 feet the service engine light remained off, but there was no acceleration still; then they took until the friday before new years to replace the part; but all is fine thus far also; but it only has been a week;
tk
tk
01-04-2008, 10:47 PM
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Well, so far so good. Chicago temps dropped (4F) and to date the check engine light is off and I have really good power. Looks like the pressure sensor and the reflash was the needed fix. Only thing now is since the reflash, I have lost about 4MPG.
I am hoping this is due to the cold and our winter ULSD fuel, and not a permanent change, as oil is now U$100.00/barrel. Hope no one else has this problem, but if so, this is the ticket.
I am hoping this is due to the cold and our winter ULSD fuel, and not a permanent change, as oil is now U$100.00/barrel. Hope no one else has this problem, but if so, this is the ticket.
