Aux Heater Swap D5z-f To D5w-s

[qswi271]

I'll start with some advice - don't do it.

 

Like many others the control board on the Aux heater on my 2005 Mark 2 Gal died. After many complains from cold children I searched and searched for a low cost solution, but failed. In the end a new D5W-S came up on ebay (Ford 37A12A02), we agree a price and the shiny unit arrived. 1 hour job I thought, 3 weeks later just got it to start - but all not well.

 

First the fittings are different so it does not fit into the Mark 2 housing, I'll post some pics later. So I managed to knock up some adapter plates, then the exhaust bracket does not fit, so I made a new one. Next problem was the electrics - the wiring is close but not quite the same, first the connect does not fit, same connector different locking tab so does not fit, I took the old connector off my duff controller and soldered it on. Then I had to connect pin 3 to +12v (pin 1). A fruitless few hours checking everything and still no heat - my VCDS does not talk to the heater, but I think it is not supposed to (still not sure here). Finally remembered reading a thread about a light bulb connected to aux heater, turns out this is to connect to the water pump output (the extra cable on the D5W-S), hey presto heat :lol:

 

Problem now is that the 12V on the Mark 2 does not appear to be switched, and the heater appears to keep the water pump on (not tried to see for how long yet). I do not want to kill the battery (sore point as my Audi A6 just had a

[qswi271]

 

Here it is a brand new heater bought for

[qswi271]

The controller unit is bolted on the end of this unit, my guess is that this is why the newer units fail, electronics do not like getting hot so sitting them on top of the diesel burner is more than a little stupid.

 

 

 

For those who do not know how these heaters work, they are very simple. The motor drives a fan that blows air over a stream of diesel, onto the glow-plug into the combustion chamber, this burns. Water passed around the chamber and warms up.

 

 

Here is the famous glow plug, took me ages to find in the new unit as they are in a totally different place. Life expectancy around 2 years, I agree with most the comments here, popping to shops on a cold day does not allow the unit so operate as designed, it should run for at least 30 minutes, not 3 as is the case in our household.

[qswi271]

 

First little surprise, the mounting points on the D5W-S are not same as the D5Z-F, so the bracket that fixes the unit to the car does not fit, time for some real engineering. And the end bracket does not fit as well.

 

 

 

[qswi271]

I made up a couple of mounting plates out of 4mm Alu I had in garage.

 

 

The left and right sides are different of course.

 

Then screwed these to the heater

 

 

The exhaust fitting also had to be made

 

 

Bent

 

 

And the whole lot mounted in old bracket

 

[MadBaz]

Looks like funhttp://www.fordgalaxy.org.uk/ford/public/style_emoticons/default/ph34r.gif

 

Here's a couple of links if you haven't got them:

D5WS

 

D5WZ

 

Wiring diagrams are near the bottom.

 

Just a couple of pointers,

 

The coolant pump on your car should be controlled by the fan relay, pin 6 green wire, no control from the heater. The bulb/resistor trick on the heater would have to be permanent.

If you want an on/off switch, use the D+, its also connected to the temp switch under the wiper arm, don't use the permanent live.

There is a diagnosis wire on the d5ws (pin 5 on both models) but it may only be read by the Eber timers, so that may have to be disconnected on the car side of loom.

 

If you need any help pls post back, off work tomorrow with man fluhttp://www.fordgalaxy.org.uk/ford/public/style_emoticons/default/sad.gif

[qswi271]

Yep I found the Eber pages, problem is that they do not really explain the way the controller for the heaters work, for example on the D5WS does the heater work if pin 3 is left floating, or does it need to pulled to +12v, I have now connected it to pin 7 which goes to +12v when the engine is running (for those who not had there head under the car for hours pin 3 and 8 are not wired into the loom on the Mark 2 Gal)

 

If I get time at lunch I may try some bigger resistors instead of the light bulb to see what current the controller thinks the water pump is connected.

 

I still can not figure out why Ford have the unit wired to a perminant +12v, seems odd as it can not turn on until the engine is running. I guess it is the 10amps that the glow plug draws when starting, which would need a bigger relay ?

 

I kind of guessed the early heaters only support the Eber diagnostics. I have it wired up to the loom (pin 5) VCDS still works on the other controllers in the car but does not see the heater (controller 18). Do I now spend

[MadBaz]

The permanent live is really for when the car is switched off and the heater is still running, it allows it to shut down properly without overheating.

Pin 3 iirc is used as an output for a telltale, it's live whenever the heater is active. I believe it gets it's signal from the flame sensor.

[qswi271]

Thanks - connecting pin 3 to 7 is a really really bad idea - the car does not turn off when you take the key out the ignition :angry:

 

Now I have found you need a load on the water pump I'll disconnect pin 3, esp since it appears to be an output, odd how it is connected to +12V on the eber pdf.

[qswi271]

Fingers slightly frozen - but the new heater works :angry:

 

I have wired a 680 ohm resistor across the water pump connector, this is enough to fool the controller into thinking it has a water pump attached. Dissipation is around 0.2W so I will replace the 1/8 watt resistor with a bigger on (probably 1W) as the little thing does gets warm. The water pump stays on about 3 minutes after the heater turns off, so no need to worry about idle load.

 

Leaving pin 3 disconnected works.

 

Looking forward to a those fast warm ups in the morning.

Edited January 11, 2012 by qswi271

[MadBaz]

Glad your sorted

[niallsan]

What was the original eber controller error on vagcom?

 

N

[qswi271]

What was the original eber controller error on vagcom?

 

N

 

Original error was glow plug shorted and glow plug open, which I thought an odd combination. I stripped down the unit tested the glow plug, which was working perfectly, everything else appeared OK, rebuilt the unit, cleared the faults, then got both open and short errors on the glow plug. At that point I concluded the controller was not working properly. Also could not get the output tests working with VCDS (I have the expensive real version, paid for itself on one service of my Audi A6).

[niallsan]

Would you be interested in posting your bad controller to Ireland to me so I could mess with it. I fixed my own controller but it was a ' dosing/metering pump short to ground' error on mine?!?!?!?

I could pay you the postage?

 

N