'Fuel Filler Cap Open' warning & Check Engine light
11-07-2010, 11:05 PM
#1
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'Fuel Filler Cap Open' warning & Check Engine light
Am about halfway through my current tank and driving today the red 'Fuel Filler Cap Open' display comes up on the MFD. As I'm pretty certain it isn't open (not come on since fill up) I pressed the 'R' button and continued on. A few hours later it came on again and I cancelled it, then noticed the dreaded 'Check Engine' light was on.
When I got home I looked at the MFD section in the manual and sure enough (given the generic nature of 'Check Engine' it notes this could come on with the filler cap being open). I turned the engine off, opened the cap, closed it and again and the light was still on, so pretty sure it isn't filler cap related.
Anyone seen this before, or have any pointers as to why this might be occurring? Perhaps symptomatic or some other issue?
Pointers are much appreciated. Thanks!
When I got home I looked at the MFD section in the manual and sure enough (given the generic nature of 'Check Engine' it notes this could come on with the filler cap being open). I turned the engine off, opened the cap, closed it and again and the light was still on, so pretty sure it isn't filler cap related.
Anyone seen this before, or have any pointers as to why this might be occurring? Perhaps symptomatic or some other issue?
Pointers are much appreciated. Thanks!
10-14-2011, 06:44 PM
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10-14-2011, 08:50 PM
#4
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2005 S500 4-Matic, 1978 450SL
If the CEL illuminates because something simple happened - like the filler cap - once the fault is corrected. it will usually reset itself after about 10 starts.
On the other hand, if the fault isn't corrected, it will remain on.
On the other hand, if the fault isn't corrected, it will remain on.
05-18-2016, 06:09 AM
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E500
Hello All,
i have same issue with the "fuel filler cap warning" on E500 2003 and check light is on, i have changed the fuel cap to new OEM one and the check light is gone for few days and again it is back now, any suggestions are appreciated!
i have same issue with the "fuel filler cap warning" on E500 2003 and check light is on, i have changed the fuel cap to new OEM one and the check light is gone for few days and again it is back now, any suggestions are appreciated!
11-17-2018, 07:19 AM
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GLE400
Am about halfway through my current tank and driving today the red 'Fuel Filler Cap Open' display comes up on the MFD. As I'm pretty certain it isn't open (not come on since fill up) I pressed the 'R' button and continued on. A few hours later it came on again and I cancelled it, then noticed the dreaded 'Check Engine' light was on.
When I got home I looked at the MFD section in the manual and sure enough (given the generic nature of 'Check Engine' it notes this could come on with the filler cap being open). I turned the engine off, opened the cap, closed it and again and the light was still on, so pretty sure it isn't filler cap related.
Anyone seen this before, or have any pointers as to why this might be occurring? Perhaps symptomatic or some other issue?
Pointers are much appreciated. Thanks!
When I got home I looked at the MFD section in the manual and sure enough (given the generic nature of 'Check Engine' it notes this could come on with the filler cap being open). I turned the engine off, opened the cap, closed it and again and the light was still on, so pretty sure it isn't filler cap related.
Anyone seen this before, or have any pointers as to why this might be occurring? Perhaps symptomatic or some other issue?
Pointers are much appreciated. Thanks!
I have the exact same issue as you, after 3~4 days it fixed automatically.
11-17-2018, 10:50 AM
#7
MBWorld Fanatic!
One of the things checked during Georgia's annual emissions inspection is the fuel filler cap. The cap is removed from the car and installed (using the necessary adapter) to the computerized test equipment. My cap failed, which meant that my 2003 S430 failed the annual inspection. Replaced the cap, got my free reinspection, and passed the test.
I had not received any error message, nor had the CEL illuminated. I can only assume that the vent mechanism within the cap can and does fail, so being loose might not be the real problem.
I had not received any error message, nor had the CEL illuminated. I can only assume that the vent mechanism within the cap can and does fail, so being loose might not be the real problem.
