How do I test my fuel level sensors? W211
05-15-2014, 01:09 PM
#1
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How do I test my fuel level sensors? W211
Hi all,
I seem to have a faulty fuel level sensor/sender in my 2005 E320 4matic wagon. Fuel gauge suddenly started reading empty - no other fault codes.
Apparently, there is a sensor on both sides and if one doesn't work this system as a whole will fail to report fuel level correctly. But before I go spending a load of money and replace both of them, I'd like to run some diagnostics first.
I've searched and I've been unable to find any info on this, only just replacement instructions.
It seems to me, I should be able to test the output voltage/signal on each of the sensors to determine if they're functioning properly.
Thanks in advance for your help.
Marc
I seem to have a faulty fuel level sensor/sender in my 2005 E320 4matic wagon. Fuel gauge suddenly started reading empty - no other fault codes.
Apparently, there is a sensor on both sides and if one doesn't work this system as a whole will fail to report fuel level correctly. But before I go spending a load of money and replace both of them, I'd like to run some diagnostics first.
I've searched and I've been unable to find any info on this, only just replacement instructions.
It seems to me, I should be able to test the output voltage/signal on each of the sensors to determine if they're functioning properly.
Thanks in advance for your help.
Marc
07-05-2014, 12:35 AM
#2
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2016 C450
There's something called a 'dekade' box where you can simulate the resistance values sent by the senders.
You need to get access to the plugs on top of the tank, unplug them and apply specific resistance values to the wires that receive the signals from the senders. You can then watch your fuel gauge to see if it moves.
This is best performed with access to and SDS. The SDS will have the specific resistance values you need to apply to see the gauge in different positions.
You need to get access to the plugs on top of the tank, unplug them and apply specific resistance values to the wires that receive the signals from the senders. You can then watch your fuel gauge to see if it moves.
This is best performed with access to and SDS. The SDS will have the specific resistance values you need to apply to see the gauge in different positions.
