405 heater control

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David Humphrey
Posts: 57
Joined: 21 Nov 2004, 01:21

405 heater control

Post by David Humphrey » 08 Aug 2005, 19:25

I have an M Reg with aircon.It was a bit cold last night so moved the heater control for a bit of warmth. I moved it back to cold today but am still getting hot air! Lets hope we don't have that heatwave because I don't seem to be able to get cool air now. Turning on the aircon doesn't seem to help either.
Any ideas would be greatly appreciated.
David

PowerLee
Posts: 1256
Joined: 01 May 2004, 19:49

405 heater control

Post by PowerLee » 08 Aug 2005, 23:03

Hi
With the ignition on but the engine not running, Move the temp slider from hot to cold slowly & can you hear any nasty clicking noises coming from the area next to the clutch pedal?
Theres a small servo motor that is for the heater water valve that controls the water flow through the heater matrix.
Also above & to the right of the glovebox is a small grill in the dash, Stick your ear agaist this & listen for a whirring sound, Thats the cabin temp sensor behind the grill.

David Humphrey
Posts: 57
Joined: 21 Nov 2004, 01:21

405 heater control

Post by David Humphrey » 09 Aug 2005, 00:49

Thanks Powerlee.
The cabin sensor makes the whirring noise but moving the lever from cold to hot does not produce any noises.I moved the lever to cold earlier in the day and it went cold but now it wont get hot! Presume it must be either the switch on on the heat control lever, the servo motor you mentioned or the valve itself.I haven't looked at the fuses yet either.
Thanks.
David

PowerLee
Posts: 1256
Joined: 01 May 2004, 19:49

405 heater control

Post by PowerLee » 09 Aug 2005, 01:13

Hi
Its most likely a dodgy connection somewhere.
To get at the servo motor:
Ok, The grey carpet trim on the drivers side of the centre consoul has 1 x small screw ( hidden well! ) & some clips holding it on, Take the screw out, Pull from the bottom of the trim to release the clips at the top & then slide it towards the front of the car & then it will lift out.
If you look up into the blackness of behind the dash, You should see the heater assy, On the side of this is the small servo motor that is held by 2 x cross head screws, If you have a short enough screwdriver it will come out easily, Theres one brown electrical connection with 5 wires in.
Theres also a lever on the heater assy that has to be just in the right position when you put the motor back on, A bit of a wiggle with the servo motor should locate it fine.
Heres a picture of the small servo motor
http://img.photobucket.com/albums/v201/ ... /Motor.jpg
The heater panel assy is fairly easy to get at if you follow the steps below.
1: Throw Haynes manual in nearest skip because the way they tell you to do it involves stripping most of the dash out & you dont need to.
2: Using a small flat blade screwdriver, pop the triangle piece of trim off at the top of the dash, DONT lever against the dash because it marks EASILY! Use a cloth between screwdriver & dash.
3: Using the cloth & screwdriver again, Pop the 3 x switches out from the front of the dash, Lever against the next switch & not the dash, Once one is out you can get your fingers in to pop the other 2 out, The connector plugs are colour coded so you wont mix them up.
4: Now undo the torx 20 screw that was behind the triangle trim & theres also one behind the hazard warning switch.
5: Now hold the radio flap at an angle, Look between the flap & the dash, See those 2 x torx 20 screws, They need to be removed too.
6: Now from the bottom, Lift the centre part of the dash away, Not to far at first! Its held by a spring clip at the top.
7: Reach behind & unplug the clock & the spare connector plug just next to it, Also unplug the alarm LED at the top of the dash.
8: The whole centre part is now free, Place it somewhere safe, Also nows a good time to do the clock bulbs!
9: The heater controls are held in by a couple of torx 20 screws & theres a spring clip ( swine to get back on! ) holding the green flap cable. Unplug the black connector plug & the whole assy can be removed from the car.
10: To put it back together after feeding all the plugs through the correct holes & connecting alarm LED & clock back up, first you need to line the spring clip up at the top of the dash & then making sure no wires are trapped it kinda pops back on.
Thers also a heater control box right up behind the glovebox, Its next to the central locking control box & ABS connector plugs, They are a right swine to get to though.
I still have a feeling its just a dodgy wire somewhere, Its just finding it that is the problem!
A 405 dash is easy once you know all the tricks to how it comes to bits & goes back together.

David Humphrey
Posts: 57
Joined: 21 Nov 2004, 01:21

405 heater control

Post by David Humphrey » 09 Aug 2005, 01:30

Hi Powerlee
Thanks for the response.
I think you are right because I have just got it to go from hot to cold without a hitch !
As you say the problem is trying to locate the fault.
David

PowerLee
Posts: 1256
Joined: 01 May 2004, 19:49

405 heater control

Post by PowerLee » 09 Aug 2005, 01:37

Hi
It does sounds like a dodgy connection then, Not something unusual on a 405!
It could be the connector plug on the back of the heater panel or the connector plug at the servo motor itself, It could also be a dodgy earth! Which for the heater is located at the bottom of the A post on the passenger side, Remove 1 x cross head screw next to the bonnet release handle ( Throw the screw away because you can never get them to go back in again ) & then unclip the black plastic sill trim, You will see the earth connection, a 10mm bolt fixes the earths to the bodyshell.
Any other odd electrical faults with the car?

David Humphrey
Posts: 57
Joined: 21 Nov 2004, 01:21

405 heater control

Post by David Humphrey » 09 Aug 2005, 01:50

Not really except for the central locking which sometimes locks immediately after opening particulaly when a passenger tries to open the door just before I plip it.I shouldn't think there is a connection though. I did take off the cabin sensor grill and the tube was partially blocked up with fluff so i vaccuumed it out.
Regards
David

PowerLee
Posts: 1256
Joined: 01 May 2004, 19:49

405 heater control

Post by PowerLee » 09 Aug 2005, 02:02

Hi
The heater & central locking are seperate units, Its when you get loads of odd faults at the same time that it points towards an earth fault.
If you do try & lift a door handle while the central locking is doing its thing the doors will lock again, I too experienced that quirk.
There are some 405 locking problems that can be easily fixed, Checking the following normally fixes dodgy 405 doors.
Have you lubricated you door latches lately? Are the doors adjusted correctly? None sitting slightly proud of the rest of the body? The door lock button isnt stiff on the door trim? Lock rods lubrictaed ok?
The central locking normally plays up by unlocking itself again when you try to lock the car, If it starts doing this then you have a duff alarm sensor on the bottom of a door latch, They are about £3ish new from Peugeot & ill dig the pin out diagram so you can find out which one it is if & when you need it.

David Humphrey
Posts: 57
Joined: 21 Nov 2004, 01:21

405 heater control

Post by David Humphrey » 09 Aug 2005, 02:19

I did take off the sill cover and look at the earth. It is a 10 mm and looks ok- not rusty so I've left it. Tried to get the screw back in to hold the cover but gave up.If the heater plays up again I will look at the connections as advised. Thanks for all your help.Its nice to know someone is around who is kind enough to respond.
David

PowerLee
Posts: 1256
Joined: 01 May 2004, 19:49

405 heater control

Post by PowerLee » 09 Aug 2005, 02:29

Hi
If you do decide to have another look at it & clean up the earth connection, Its a good idea to disconnect the battery first.
Before you do that you need to know the radio code & if its an airbag equipped 405 to shut the alarm system down.
Ive also never managed to get the screws back into those trim on both the 405s ive worked on, Id love to know how they done that one at the factory.
Ive had most of the normal 405 problems in the 6 years of 405 ownership ive had of 2 different 405s, I dont mind sharing information & my 405 knowledge with a fellow Peugeot owner.
By the way, Does your 405 have an airbag fitted?

David Humphrey
Posts: 57
Joined: 21 Nov 2004, 01:21

405 heater control

Post by David Humphrey » 09 Aug 2005, 02:45

No it doesn't have an airbag.Looking at the screw it looks as if it might be self drilled using a special tool perhaps?
David

PowerLee
Posts: 1256
Joined: 01 May 2004, 19:49

405 heater control

Post by PowerLee » 09 Aug 2005, 02:52

Hi
No airbag means it has the SERIOUS security flaw! I WONT reveal what it is on a public forum.

Mark_Casey
Posts: 7
Joined: 16 Dec 2004, 16:16

405 heater control

Post by Mark_Casey » 11 Aug 2005, 03:14

AAGH! As I'm a non-airbag 405er that last statement left me relaxed and comfortable...not.

PowerLee
Posts: 1256
Joined: 01 May 2004, 19:49

405 heater control

Post by PowerLee » 11 Aug 2005, 03:23

Hi
The Australian spec 405s have an even WORSE security system then the U.K. spec cars.
Also you never got the shielded front door locks either.
Only June 1995 onwards U.K. spec 405 owners with a petrol engine can breath a sigh of relief on the security front, Peugeot managed to get all but one of the flaws out of the system.
The petrol engine keypad immobiliser from June 1995 ( The one with an "S" button ) is still Thatcham Cat 2 approved.