Various woes (and heater)
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Newbie
Joined: Dec 2002
Posts: 6
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From: UK
260e
Various woes (and heater)
1) Thanks for the previous help on my heater (or lack) problem. I located the "Duo-valve" and tried removing & refitting the plug a few times. The situation is now that the passenger side gets hot, the drivers side does not. When I touch the duo-valve, one side is too hot to touch, the other is warm.
The haynes manual I own is vary basic when it comes to the heating system & doesn't have any information regarding the A/C system.
Can I remove the cover of the duo-valve to see if it is stuck or does it contain A/C fluid ?
Is it possible for anyone to e-mail me, or point me to a web-site where I can see how to use the heating system (in English) as I do not have the owners handbook.
2) When braking, the revs drop very low & then pick up again to idle speed, is this normal ? somestimes, when sat in traffic, the revs go up & down between very low & about 900, although it does not stall, it feels as if it will.
3) My battery goes flat after about 2-3 days of non use. By removing fuse 9, this problem dissappears. The only differences I can tell are that the clock now does not run when ignition is off & the interior lights do not come on unless ignition is on. All my interior lights are definately turned off when leaving vehicle, can anyone suggest a starting place to check out the flat battery so I can have a clock !
Also, can anyone recommend a supplier of parts in the UK that are reliable & cheap (I need shockers & some trim bits)
Many thanks for all your help
Mike
The haynes manual I own is vary basic when it comes to the heating system & doesn't have any information regarding the A/C system.
Can I remove the cover of the duo-valve to see if it is stuck or does it contain A/C fluid ?
Is it possible for anyone to e-mail me, or point me to a web-site where I can see how to use the heating system (in English) as I do not have the owners handbook.
2) When braking, the revs drop very low & then pick up again to idle speed, is this normal ? somestimes, when sat in traffic, the revs go up & down between very low & about 900, although it does not stall, it feels as if it will.
3) My battery goes flat after about 2-3 days of non use. By removing fuse 9, this problem dissappears. The only differences I can tell are that the clock now does not run when ignition is off & the interior lights do not come on unless ignition is on. All my interior lights are definately turned off when leaving vehicle, can anyone suggest a starting place to check out the flat battery so I can have a clock !
Also, can anyone recommend a supplier of parts in the UK that are reliable & cheap (I need shockers & some trim bits)
Many thanks for all your help
Mike
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Joined: Feb 2002
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From: Southern California
2001 E 320
Well on my old car, the battery couldnt hold power because one of the compartent walls were damaged and would mix with another compartment in the battery. But I dunno if this is the same bc you said if u take out the fuse it then doesnt happen.
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Joined: Jan 2003
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From: England
300TD 1992
Do not try to remove the cover of the duo valve. They control water, not ac fluid.
The duo valves operate on a pulsed 12v supply. They are pulsed according to the temperature required in the passenger compartment. They are effectively a valve that opens and closes to allow controlled amounts of hot water to pass through and into the heater matrix. They are fed by a water pipe that is pumped from the engine side of the thermostat housing. The small pump is there to feed the system when it is on tickover. Given that one side is working, it is likely that the pump is OK, as is the feed from the engine. The control panel quite often is the cause of the problem and costs a small fortune to replace. However, it could be a failed duo valve which are also prone to failure. Check the voltage pulses across each of the valves at different temperature settings on the temperature wheel on the control panel in the car. This will give you an indication of where the fault may be.
Potential second hand suppliers of these parts in the UK are Damas in Chesterfieldand or The Garage near Manchester.
Not sure about the fluctuating revs. Is it a petrol or a diesel?
Regarding the flat battery problem. Check the current draw from fuse 9, then check the current draw from each of the elements from fuse 9 and you will find the offending ancillary component.
The duo valves operate on a pulsed 12v supply. They are pulsed according to the temperature required in the passenger compartment. They are effectively a valve that opens and closes to allow controlled amounts of hot water to pass through and into the heater matrix. They are fed by a water pipe that is pumped from the engine side of the thermostat housing. The small pump is there to feed the system when it is on tickover. Given that one side is working, it is likely that the pump is OK, as is the feed from the engine. The control panel quite often is the cause of the problem and costs a small fortune to replace. However, it could be a failed duo valve which are also prone to failure. Check the voltage pulses across each of the valves at different temperature settings on the temperature wheel on the control panel in the car. This will give you an indication of where the fault may be.
Potential second hand suppliers of these parts in the UK are Damas in Chesterfieldand or The Garage near Manchester.
Not sure about the fluctuating revs. Is it a petrol or a diesel?
Regarding the flat battery problem. Check the current draw from fuse 9, then check the current draw from each of the elements from fuse 9 and you will find the offending ancillary component.
Last edited by gvbenz; Jan 11, 2003 at 05:41 PM.
