Cabin Heater Problem in RX Patrol

[Ddan]

Hi Guys,

Looking for advice on this heater problem. Here's a description of what's happening.

With dashboard lever set to cold, switching fan on produces cold air. Moving lever to hot, produces hot air, but it quickly cools down (about 2mins or so). I'm guessing that the lever mechanism is working but the hot water isn't flowing. I'm assuming that the hot water should flow through a small coil/radiator somewhere behind the dashboard or in the assembly under the glove box where the fan is located.

Does anyone have any thoughts on where to start? I've never worked on this area before so maybe the first question should be, is it a DIY project?

Thanx

Ddan

[threedogs]

Small coil/radiator could be clogged with mud [flush required] or the heater resistor is knackered?, all I can come up with at the moment. But somewhere to look

[Ddan]

Thanx.

As I said I'm new to this area of maintenance/repair, can I backflush with a water hose if I disconnect in and out hoses to heater system? Also where would I find the heater resistor?

Ddan

[threedogs]

Yes and make sure heater lever is on hot so whole lot gets flushed , not sure where other thing is on a patrol someone wiser might be able to help there or look in manual

[Ddan]

Ok, tried backflush, water was clear and flowing freely, so still looking for fix. Anyone have any ideas? Does the hot/cold lever just work an air baffle and if so, does this mean hot water flows permanently through heater section?

Ddan

[macca]

Ok, tried backflush, water was clear and flowing freely, so still looking for fix. Anyone have any ideas? Does the hot/cold lever just work an air baffle and if so, does this mean hot water flows permanently through heater section?

Ddan

G'day Ddan
I reckon the hot water flows through the heater continuosly, we have a glind shower that works on the heater piping and it heats no mater where the heater controls are set.
There must be an air baffle, mine doesnt seal and the air out of the vents is warm all the time. Got sick of it in summer especially and fitted an electric ball valve to the pipes.

Cheers Macca

[Ddan]

G'day Ddan
I reckon the hot water flows through the heater continuosly, we have a glind shower that works on the heater piping and it heats no mater where the heater controls are set.
There must be an air baffle, mine doesnt seal and the air out of the vents is warm all the time. Got sick of it in summer especially and fitted an electric ball valve to the pipes.

Cheers Macca

Thanx for confirming that Macca, I'm starting to think that it must be the air baffle only moving a small amount from the closed position. Any idea where the baffle is? Presumably right behind the central dash or somewhere down near the fan?

Ddan

[johno90]

Theres a thing called a blend door in the heat box that allowes air to either go through the heat core or around it through another channel. check that it is getting full movment of not slightly moving back after setting it to hot.

[johno90]

Oo and also could be the cable needs adjusting :)

[Ddan]

Theres a thing called a blend door in the heat box that allowes air to either go through the heat core or around it through another channel. check that it is getting full movment of not slightly moving back after setting it to hot.

Hi and thanx for that info. Unfortunately I don't have a manual so can you tell me where the heat box is? Is it behind the central dash?

Ddan

[johno90]

starts behing the glovebox and goes behind the centre section, blend door is near the cross over of the 2, easy way to find it is move your hot cold knob and look at what the cable is moving and follow it down.

[macca]

Sorry mate missed your post, its righ in the middle above the transmission tunnel.

Real awkward spot to get to I reckon.

[threedogs]

You might also find that the cable has simply unclipped and just needs to be re fitted.
Might need an 8 yo with long skinny arms

[johno90]

seriously try working on new cars, you need like a go go gadget arm to bend in 5 points to do anything these days.

[Ddan]

Thanx guys, will have a closer look now I know where to look. And for threedogs, I used to have one of those in my toolbox....unfortunately he grew up.

Ddan