Mercedes S320 CDi 2004 May Reg
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From: Bedford UK
S320 cdi 2004
Mercedes S320 CDi 2004 May Reg
Hi All,
I have a S320 CDI (UK) first registered 2004 and it has been fine up until recently when it has developed a series of faults.
1. Automatic wipers seem to have lost/intermittent sensitivity, the screen has to be "drowned" before they activate and yet sometimes they start when there's no rain!!
2. Heating system wont get much above 22C.
3. A/C red light permanently on and no cooling effect on low temp settings
4. Lights above vanity mirrors in front wont switch on
5. "Coolant - drive to workshop" indicator flashes on intermittently when the coolant level is fine.
It had developed a leaky water pump and was previously showing the the "Check coolant" indication and this was replaced. The independent service chap who replaced the pump said that the leaky water pump would cause the heating to not work as there was not enough "head of water" to get to the heat exchanger. The water pump was changed and the heating still isnt working and the warning now is the "Coolant drive to workshop" warning intermittently, though I have checked and the coolant level in the expansion tank is fine.
At no time in all of this did the engine run hot, in fact the temp guage never got much above 75c
The independent guy who serviced it for me said that the lights and wipers and the intermittent warnings may be a problem with with a Signal Acquisition Module (??) and this would need replacing and programming at a MB main service centre at a cost of £450 ish
The water pump change, two new pollen filters and a new cabin air filter came to £500 so I'm jsut wondering if there's any other suggestions or ideas from the wise on here before I take it into my local MB dealer/service centre.
I phoned him to tell him about the AC light which had worked fine before it went in and his answer was that it was just coincidence and they had not worked on the AC (yet they had changed the cabin filters??!!)
Many thanks for any pointers
Jim
I have a S320 CDI (UK) first registered 2004 and it has been fine up until recently when it has developed a series of faults.
1. Automatic wipers seem to have lost/intermittent sensitivity, the screen has to be "drowned" before they activate and yet sometimes they start when there's no rain!!
2. Heating system wont get much above 22C.
3. A/C red light permanently on and no cooling effect on low temp settings
4. Lights above vanity mirrors in front wont switch on
5. "Coolant - drive to workshop" indicator flashes on intermittently when the coolant level is fine.
It had developed a leaky water pump and was previously showing the the "Check coolant" indication and this was replaced. The independent service chap who replaced the pump said that the leaky water pump would cause the heating to not work as there was not enough "head of water" to get to the heat exchanger. The water pump was changed and the heating still isnt working and the warning now is the "Coolant drive to workshop" warning intermittently, though I have checked and the coolant level in the expansion tank is fine.
At no time in all of this did the engine run hot, in fact the temp guage never got much above 75c
The independent guy who serviced it for me said that the lights and wipers and the intermittent warnings may be a problem with with a Signal Acquisition Module (??) and this would need replacing and programming at a MB main service centre at a cost of £450 ish
The water pump change, two new pollen filters and a new cabin air filter came to £500 so I'm jsut wondering if there's any other suggestions or ideas from the wise on here before I take it into my local MB dealer/service centre.
I phoned him to tell him about the AC light which had worked fine before it went in and his answer was that it was just coincidence and they had not worked on the AC (yet they had changed the cabin filters??!!)
Many thanks for any pointers
Jim
Junior Member
Joined: Oct 2005
Posts: 42
Likes: 1
From: Belfast, Northern Ireland
2007 w221 Brabus D6 III S320CDi LWB,2003 S500 LWB & 1999 W202 240 Elegance
There are two pollen filters and two charcoal filters, they are changed in the cabin, it has nothing to do with the A/C as such, A/C probably needs recharged from under the bonnet.
The coolant light might have something to do with the washer fluid, I heard somewhere the sensors are connected ? (I may be wrong)
Try cleaning the windscreen where the wiper/light sensor is, its behind the rear view mirror.
Alan
The coolant light might have something to do with the washer fluid, I heard somewhere the sensors are connected ? (I may be wrong)
Try cleaning the windscreen where the wiper/light sensor is, its behind the rear view mirror.
Alan
