OK, this has me stumped.

It is a 8/01 S type 3ltr SE.

There is no heat inside the car, no matter what setting is requested.

It did work, just fine, now zip.

What I have done today:

Coolant level is OK.
Pipes TO the firewall are HOT.
In cabin sniffer is clean, it was dusty, not dirty.
There are NO codes, nothing.

Based on this, I reckon the DCCV is fine, and maybe the heater core is blocked??. Although I am told this is not common on this model.

With the engine running, and my hand ON the DCCV, and the spouse changing temp settings, I can feel the DCCV clicking, and the fact I have hot pipes to the entry point to the cabin indicates it is doing what it should.

What mysterious item is going to drain my wallet this time, haha. At least the car goes to sleep now, and that cost me nothing to fix.

As always, thanks in advance.

 

See my post above. Hot pipes to bulkhead but 19 mm return cold until side 19mm pipe comes in then hot. So i suspect a tap /switch assembly next to heater core is not switching so question is why..sensor, mechanical broken wire... Worked for 2 hours last 2 months and then worked perfectly. water pump ok... now looking for a diagram Paul

 

Even if you had codes they'd be in CCM/RCCM which needs dealer-type software to read.

I'd guess DCCV stuck closed. Everything else is probably more hassle

 

If I can chime in - either CCM or possibly the servo motor controlling the air flow between the heater core/evaporator is stuck/malfunctioning.

 

Thanks something to do with a servo motor switch sounds right. Since hot water is getting around and there is power to pump and Heater valves they are not shut closed or else no hot water. Default is open so that fits with heat to Core. Now: Can I find a diagram to know what to check trigger or fix. Paul

 

Grant, does your model have two 19 mm return pipes. Clue to my issue is the 19 from centre bulkhead is cold and the entry from the driver side 19mm is hot. It joins the centre 19 return where the centre pipe turns to go forward: and therefore the return pipe is hot on way to front dccv. I though the two smaller inlet pipes were L & R for the dual CC and didn't know there were two 19 m returns. I need a schematic to comprehend switch system under dash. Paul

 

JTIS is free here and is workshop manual.

 

I found a pic of a heater assembly showing two pipes in and one out so dont know why I have extra 19 mm pipe from side. The pic shows the top flap that would have to open to let the heat flow..so maybe that servo system is out of action. Saw a thread about a broken tooth on the drive that could explain it. As to getting to the unit that looks a big job for Ron...
My second plug in electric heater arrives this week. 22C today so winter is over and my aircond works well.... Paul

 

Your shooting in the dark!

Get the JTIS as it has diagrams and troubleshooting guidelines. The car is too complicated to work on without factory documentation.

We have the JTIS and the JEPC for free on this site. These are the two Factory items that have everything in them.
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