lagonda 41 Posted April 15, 2007 Just to be clear, this isn't the speed control, which lives behind the heater knob in the middle of the dash. The control unit is screwed to the heater blower motor housing, & has a 4 terminal multiplug going into it. I've identified it as the reason my heater fan wasn't working. I've removed the unit & found it a bit corroded up & dirty as the upper part is a finned aluminium heat sink which is cooled by the (always cold at this point) air blown over it. After cleaning, I noticed there is a peculiar sprung connection/tab holding a tiny metal disc against the aluminium of the heat sink. Anyone know what that's all about? I've removed the disc & cleaned it, & the heat sink area & tab, & the heater blower now occasionally works. I wasn't able to clean the tab or heat sink area very well ... pressing the tab against the disc sometimes gets things going, but not always. I can progress to unsoldering the tab to clean things more thoroughly ... or should I look to clean /repair something in the plastic casing between the heatsink & multiplug terminal socket? It does sound like there may be a relay in there. If that's the case, how do I dismantle it? At first glance it just seems to be held in place by sealant, so do I just cut that way & pull the unit from the housing? Share this post Link to post Share on other sites
Edp 67 3 Cars Posted April 15, 2007 Pointless, just nick one from a scrappy in my opinion. Share this post Link to post Share on other sites
Super Josh 4 Posted April 15, 2007 As Ed says, just fit one from a scrappy Josh Share this post Link to post Share on other sites
lagonda 41 Posted April 15, 2007 Yes but there's no fun in that, not many scrappies around here & knowing my luck I'll find that one's just as bad! Share this post Link to post Share on other sites
Mikey S 29 1 Cars Posted April 15, 2007 Yes but there's no fun in that, not many scrappies around here & knowing my luck I'll find that one's just as bad! you can buy them new from gsf etc for not alot of cash, 20 odd quid plus vat if my memory serves me correctly. Share this post Link to post Share on other sites
inferno 1 Posted April 15, 2007 thank your lucky stars u dont have a c5 , there around 70+vat trade! Share this post Link to post Share on other sites
Edp 67 3 Cars Posted April 16, 2007 Yes but there's no fun in that, not many scrappies around here & knowing my luck I'll find that one's just as bad! Well i live about 15 mintues from you and theres a scrppy about 10 mintues from me. 25 minutes and you will have a new motor resistor plus any other goodies you can get your grubby hands on Share this post Link to post Share on other sites
Mattsav 1 Posted April 17, 2007 I spent hours taking mine apart and soldering wires across the broken tracks. It worked for 2 days and then stopped again - Bloody French cars! Share this post Link to post Share on other sites
lagonda 41 Posted April 17, 2007 Oh well, I'll pull it apart at the weekend & report progress. Can always get a new one from GSF if need be. Talking of progress & your comments Mattsav ... I've got a 1951 Riley with a heater, an expensive optional extra in those days. The heater blower motor is controlled by a rheostat, an adjustable resistor. So ... after 40 years "progress" how is it that Peugeot needed to use a "speed control" and a transistorised heat sinked control unit to do the job that a rheostat did RELIABLY 40 years before? Share this post Link to post Share on other sites
christopher 5 1 Cars Posted April 18, 2007 Well Yes replacing the whole thing will do it.... Or if you are cheap like me... gently remove the disc try not to bend the springy thing that hold it down Then sand the disc down with fine sandpaper on both sides Then take the sandpaper and gently sand the bottom of the springy thing that hold the disc on Scrape the area teh disc is on with a thin screwdriver Then take some thing pliers and bend the springy thing first out and then in so it grabs tight. Then gently hold the pringly thing back and replace the disc. It is importnant there is a decent electrical contact. Well it worked for me and mines from 1988 Share this post Link to post Share on other sites
lagonda 41 Posted April 20, 2007 Thanks Christopher. I have cleaned the disc thoroughly but not too happy with my efforts on the springy thing & seating area on the heat sink. Might have a go at unsoldering spring arm to move it to one side while I clean heat sink area. As you say a bit of extra kink in the spring won't go amiss whilst it's loose, then I can resolder it in original position. Looks like it's rivetted as well so suspect it won't come away once solder's melted. Not sure if that will completely solve the issue as I suspect there's a relay of some sort in the lower part of the unit which might be playing up. Share this post Link to post Share on other sites
Super Josh 4 Posted April 20, 2007 Not sure if that will completely solve the issue as I suspect there's a relay of some sort in the lower part of the unit which might be playing up. The relay is only present on the 5 pin modules, and it bypasses the transistor at full speed to give the blower motor that little bit of extra umph. The usual problems are either corroded contacts or a defunct transistor. Josh Share this post Link to post Share on other sites
lagonda 41 Posted May 15, 2007 I've at last got round to looking at this, and, Christopher, it's pretty much as you said. Unfortunately I tried to do the job "properly", and for my trouble ended up pulling the spring contact with its stupidly tiny rivet out of the circuit board. Aralditing it back in didn't work, so I've ended up screwing a large fibre (non conducting) disc with a self tapper through one of the transistor rivets. That bears down on the spring contact & ensures proper instead of feeble contact. Now, after all that, the heater fan works every time .... at last. Wish I'd followed your instructions & just tweaked spring contact with pliers, but at least I can confirm to others that that is the way to go. At least removing the contact completely gave me the chance to clean it & the contact surface on the heat sink thoroughly! Share this post Link to post Share on other sites
christopher 5 1 Cars Posted May 15, 2007 I've at last got round to looking at this, and, Christopher, it's pretty much as you said.Unfortunately I tried to do the job "properly", and for my trouble ended up pulling the spring contact with its stupidly tiny rivet out of the circuit board. Aralditing it back in didn't work, so I've ended up screwing a large fibre (non conducting) disc with a self tapper through one of the transistor rivets. That bears down on the spring contact & ensures proper instead of feeble contact. Now, after all that, the heater fan works every time .... at last. Wish I'd followed your instructions & just tweaked spring contact with pliers, but at least I can confirm to others that that is the way to go. At least removing the contact completely gave me the chance to clean it & the contact surface on the heat sink thoroughly! Glad you got it fixed in the end:-) I had to do mine a couple of times before it stayed good Share this post Link to post Share on other sites
dani959 0 Posted June 2, 2007 Repaired mine today. The metal disk was not making a good contact with the arm/board. cleaned it and it's fine now. Maybe next time I'll solder it completely to the board. The transistor was completely rusted on the surface, but seems to be still working fine... Share this post Link to post Share on other sites
