X308
Member
- Joined
- Dec 30, 2017
- Messages
- 15
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- Location
- Mostly in the Bobby Moore Stand
- Your Mercedes
- w211 2003 2.7cdi
My mother in laws E270cdi '03 has for some time now been getting the convenience warning, usually rectified following a start within a minute or so.
As she has stopped driving I have sort of inherited the car pending sale so I have decided to spend a little time doing the odd bits that seem to be an issue.
Last week I sorted the glow plugs and relay. I also changed the thermostat as the interior dial had been reading 60 degrees rock solid (however accurate that may be?)
I then had a fiddle with my amp meter pulling a few fuses here and there. Initial inline reading was 2 or three amps with a surge to 10 amps for good measure. Within a minute this had settled to 0.08amp, which whilst slightly high, I thought was OK. The interior (and meter) volt reading was a steady 11.75V rising to 13.8V @ 1200rpm which considering the messing around I had been doing I was not concerned about the voltage, although despite an apparent lack of drain the battery never seemed to get charged fully. There appeared to be no evidence of an unexpected drain.
Having replaced the thermostat and charged the battery I am now getting 12.3volt rising to 13.8 volts @ 1200rpm. This has been consistent for 5 days.
Conclusion:
The lack of temperature in the coolant in turn lead to constant activation of the heater booster (runs off 200amp fuse in right hand footwell (L or RHD)) thus draining the battery to an extent the alternator was unable to rectify.
From what I can gather the booster is in operation at temperatures under 80 degrees.
Comments welcome,
Regards,
X308
As she has stopped driving I have sort of inherited the car pending sale so I have decided to spend a little time doing the odd bits that seem to be an issue.
Last week I sorted the glow plugs and relay. I also changed the thermostat as the interior dial had been reading 60 degrees rock solid (however accurate that may be?)
I then had a fiddle with my amp meter pulling a few fuses here and there. Initial inline reading was 2 or three amps with a surge to 10 amps for good measure. Within a minute this had settled to 0.08amp, which whilst slightly high, I thought was OK. The interior (and meter) volt reading was a steady 11.75V rising to 13.8V @ 1200rpm which considering the messing around I had been doing I was not concerned about the voltage, although despite an apparent lack of drain the battery never seemed to get charged fully. There appeared to be no evidence of an unexpected drain.
Having replaced the thermostat and charged the battery I am now getting 12.3volt rising to 13.8 volts @ 1200rpm. This has been consistent for 5 days.
Conclusion:
The lack of temperature in the coolant in turn lead to constant activation of the heater booster (runs off 200amp fuse in right hand footwell (L or RHD)) thus draining the battery to an extent the alternator was unable to rectify.
From what I can gather the booster is in operation at temperatures under 80 degrees.
Comments welcome,
Regards,
X308
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