fuel gauge problem, need coding?? (2 different sending units on same car?!)
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Joined: Dec 2005
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1985 500sec, 1991 500sel, 02 clk430
fuel gauge problem, need coding?? (2 different sending units on same car?!)
hi guys, im having a problem with a 2003 c320 i recently got, the fuel gauge on the car does not work properly.
i checked the gauges through my scanner (i have a maxidas ds708 does a lot of stuff but a little limited coding wise) and they work correctly.
now here is where it gets interesting, when we checked the fuel tank we noticed there are 2 fuel pumps, and each one have a different type of sending unit
i ordered a replacment fuel pump with sending unit from the parts store but but when i installed it (on the right side pump) the guage would only work half way.
when looking into alldata i read that there are 2 different kinds of sending units (one film type and one magnetic) that can be installed on these cars and that they have to be coded into the insturment cluster and the SAM module, is that true?
the sending unit on the left is the film type i think and the one that was installed on the right is the magnetic, the new one i got installed on the right is the film type.
im so confused with this problem any help would greatly be appreciated
i checked the gauges through my scanner (i have a maxidas ds708 does a lot of stuff but a little limited coding wise) and they work correctly.
now here is where it gets interesting, when we checked the fuel tank we noticed there are 2 fuel pumps, and each one have a different type of sending unit
i ordered a replacment fuel pump with sending unit from the parts store but but when i installed it (on the right side pump) the guage would only work half way.
when looking into alldata i read that there are 2 different kinds of sending units (one film type and one magnetic) that can be installed on these cars and that they have to be coded into the insturment cluster and the SAM module, is that true?
the sending unit on the left is the film type i think and the one that was installed on the right is the magnetic, the new one i got installed on the right is the film type.
im so confused with this problem any help would greatly be appreciated
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Joined: Mar 2007
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From: VA
THE C350
I am no expert on this topic but I do know that they had two types of fuel sending units. And if you change to a different type yes you do have to code I believe its not the IC but the rear Sam but I could be wrong. What surprises me is I thought the change over to the new style was 02. The dealer has said to change the parts in pairs to prevent issues I guess I do know some get away with only doing the bad part but have seen others with the same issue your having.
BTW you only have one pump the other side is just a sending unit.
BTW you only have one pump the other side is just a sending unit.
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Joined: Aug 2014
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w203 C240-2001
He is right,
When u change the fuel sender unit (especially when u only do it for one side of the car),
You gonna need to recode/reprogram it on rear sam...
Mine used to puzzled me. The gauge show empty when it's full and full when the tank is actually empty,
So when i use the car, the gauge will go up, not down, haha.
It fixed after reprogramed. Although i ends up changing both side of the units using same brand (bosch) because the age is coming~
When u change the fuel sender unit (especially when u only do it for one side of the car),
You gonna need to recode/reprogram it on rear sam...
Mine used to puzzled me. The gauge show empty when it's full and full when the tank is actually empty,
So when i use the car, the gauge will go up, not down, haha.
It fixed after reprogramed. Although i ends up changing both side of the units using same brand (bosch) because the age is coming~
