Heater Booster fault?????

[jetjockey]

Thanks all. Brilliant work!

Crikey.

That does look a big Job, possibly too big for me to handle..

Right........... I think you are correct Alex, next thing is the circuit diagram.
If you could find something tomorrow that would be great. I have 10 days off work at the moment and was planning a few days away. However..... It would be great to use the time to get this sorted.

With a circuit diagram i can work out whether it needs to come out or whether the fault is in the actuation circuitry.

We're getting there. Gerald.

 

[Alex Crow]

ok gerald, the wiring.

the heater booster (R22/3) is located inside the climate housing, and is a huge job to get at. it has very simple wiring - live + earth (both permanent, ie circuit 30 and 31), and control wiring. the controk side of things consists of a 3 wire ribbon, wired to the AAC unit in series with all the servo motors - forget doing any tests here, they will only be possible through the AAC module with star. the live and earth connections are both located under the driver's carpet, the earth is W15/1, and will be brown cable aprox 25mm2. the live comes from fusebox f32 (under carpet near drivers left foot rest), is a black cable 25 mm2, and fused by either a 150 or 200 amp fuse (f68) inside the f68 module.

realistically,will only be possible to test the live and earth supply, and live tests through star. to test the element manually would require a full dash removal etc.

 

[pomm001]

Hi Alex

Thanks for that. Point taken.

What you say makles sense about the engine running. Just home from the daughters (that cost me) and have tried the system again. This time called up battery voltage display (service) in cluster and showing 13.1 volt.
Pressed the rest button, same story as this morning. Auxilary pump down by driverside headlamp starts up and blower starts on low speed. After two minutes - cold air still.

Just going out to start the engine and try again.

Just wish I knew what to expect. Does the air blower come on at full speed and blow hot. Or is it more of a warm breeze.





Actually, that's just given me another idea. I'm going to start the engine and select "Demist" on the front screen. Back in a minute. :idea:

Cheers, Gerald.

out of interest how do you call up the battery voltage from the instrument cluster
many thanks

 

[djb]

out of interest how do you call up the battery voltage from the instrument cluster
many thanks

seehttp://forums.mercedesclub.org.uk/showthread.php?t=17069 post 4 for details

 

[xavierx]

Hello Gerald.

I also have problems with my Heater booster.

Mine does not work most of the time (suspected weak main battery) but when it does work it is very noticeable.

I can start the car in -5degree's, close the doors, go and unlock my gates, get back in the car a minute later and it is nice and toasty warm. That only happens 1 in 10 times at best though

 

[jetjockey]

Hi Alex.

Thanks for the info. Armed with that I thought I would have a dig about.

The only changes in my vehicle are that the positive supply is red. The fuse is not shown in the following link describing the Dual battery system on the W211. http://www.mercedestechstore.com/pdfs/W211_technician/319 HO Dual Battery (ACB - ICC) 11-29-02.pdf

However, on my E320 Cdi there are an extra two fuses not shown in the article. They are numbered F68 and F69. You can see in the moulding where provision is made for them to be fitted (left of F70 and F71).

As you say, the power goes from the fuse direct to the positive heater terminal with no external switching. It must be the case therefore, that the Switch / Controller must be integral to the Heater Booster and must reside up inside the dash (read totally inaccessible) .

In my case the fuse was intact and the power was present.

After reassembling everything the "Stored and Current" Heater Booster fault then cleared whereas before it had refused!! :evil: Grrrr!

Anyway, it has worked ever since and is very welcome. It does hammer the battery though.

Cheers, Gerald.

 

[Alex Crow]

Anyway, it has worked ever since and is very welcome. It does hammer the battery though.

Cheers, Gerald.

sounds like a result gerald? did you tweak the fuse terminals or anything else that could have helped?

 

[xavierx]

Wow, sounds as simple as a loose connection then. Congrats on the simple fix

 

[jetjockey]

The only thing I can think of is maybe I moved something behind the dash board. Certainly the 25mm cables were secured solidly to the rest of the mechanism.

Purely as an aside, where can I find an info sheet for the fusebox under the bonnet? I have found the sheet in the car but that only lists the fuses in the loadspace fusebox and the one in the end of the dashboard. I can find nothing on the relays in either of those fuse boxes or anything at all on the one under the bonnet.

Thanks, Gerald.

 

[television]

The ECU for this heater is easy to take out, and just under the dash,,it could be a poor connection in that

F68 is for the heater booster with engines 646, 647 and 648
F69 is for the glow plugs

 

[jetjockey]

Hi Malcolm

What doe F58 feed? Is it the controller?

The Permanent feed for the Heater Booster in my 211 defo came off F68 on Pre Fuse Box F32 under the carpet in the drivers footwell. Right next to F69 for the Glow plugs.

How does one get at the controller? I could see no sign of anything else in or around the heater element. BTW the heater element was enclosed in the heater / mixer box of course.

Thanks, Gerald.

 

[television]

Sorry that was a typo and I forgot to change it,,it is F68

I can print off the instruction later in the day for the control unit,,it was quite doable with ouit much work

 

[jetjockey]

Thanks Malcolm.

That would be very much appreciated.

Thank heavens that F58 was a typo. I can't keep up with the number of fuseboxes on this car without Ghost fuses making an appearance. :Oops::lol::lol:

As an aside, in addition to the Controller removal instructions, Would you have any info on the Fuse box under the bonnet Malcolm? I cannot find a reference to it anywhere.
Thank you, Gerald.

 

[jetjockey]

Hi Malcolm.

Sorry to trouble you.

You mentioned that you would print off removal instructions for the Heater Booster controller a few days ago.

Did you have any luck?

Thanks, Gerald.

 

[jetjockey]

Bump.....?

 

[xavierx]

Did you pull apart the dash enough to get to the heating element? How big of a job was that?

I miss mine working

 

[rpe2]

Did you know that the booster only works with the A/C switched on

 

[xavierx]

Yes,

Mine worked every now and then .... now it doesn't work at all. My climate control is always set to auto

 

[romi7519]

Hi all!

Been reading this thread with interest. I have a 2002 E270 CDI which keeps draining the battery. The battery gets completely drained by the morning and needs jump starting. Changed battery 3 times and it's still the same.

Had an electrician look at it and he has confirmed a voltage drop but he doesn't know what's causing it..

Used Star diagnostics and this came up; current and stored fault (R22/3) Heater Booster Electrical Fault.

Further digging showed;

PTC Heater Booster Faulty
Actual current 255 Amp

Any ideas please?

 

[television]

Just pull the fuse and drive without it or have it replaced