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How to: Swap your heater matrix


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Hopefully this will get the thumbs from the more tech guys. Had to do a matrix change today for a customer, so I thought i'd do a rough guide on the process. I know some of you look at this as quite a daunting task, but with the right tools and a little patience, jobs a good un. :)

 

You will need: 10mm Socket, 12mm Socket, 14mm Socket. 10mm Spanner, preferably ratchet type. Cross and flat screwdrivers, medium size. Large pliers, long nose pliers.

You will also need to get the gas pumped out of your aircon system. DO NOT try this yourself, this stuff is nasty, very nasty.

 

Ok, first remove the sill strips from both sides, these just pull out of the clips. Then carefully remove all the dash panels in this order, starting with the shifter surround which just pulls up, then the top dash panel with the odo and warning lights, this is held in by 5 x screws along the top. Pop out the dial surround panel, then unscrew the last couple of screws on the left and right panels and pop them out. Once poppoed out, you can just get your hand in to unplug the heater controls, etc......

 

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Once thats done, unscrew the 2 x screws each side of the shifter, one behind it, and 2 x in the center compartment, then slide the center console up the handbrake and out the way. Then open the upper glovebox, pop off the 2 round covers to reveal the screws/8mm bolts and undo them. Under the lower glovebox you'll see 2 10mm bolts, undo them then open the glove box to reveal 2 x screws on the top edge and undo them. Give the glove box a gentle tug to pull it out, undo the light plug and pull the lower glove box out of the way. Then looking up to the underside of the upper glovebox, you'll see 2 more gold coloured screws/8mm bolts, undo them and the upper glove box will just pop out....

 

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On top of the dash vent on the far passanger side there is a smaller vent held in by 1 x screw, undo this and pop the vent out to reveal the hidden dash bolt everyone misses..... :D

 

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Next, in both footwells you'll see a 10mm bolt holding in the earths for the dash loom, undo them.....

 

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Now looking up underneath the steering columb, you'll see 4 black 14mm nuts, undo them and the columb will drop to the floor.

 

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Edited by Jezz (see edit history)
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The part numbers for those two pipes are: 87248-14240 87248-14230 You can only change them with the heater unit removed from the dash.

If its the original matrix id be changing that as well if you can still get them, there's one sold by  Demisterman but i've read its not as good a unit as the OE matrix in its performance 

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Next you need to undo the 2 17mm bolts holding in the handbrake. If you dont do this, the dash will not clear it on removal.....

 

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Now moving onto both footwells, passenger side has 3 plugs to remove for the dash loom, one blue, 1 big orange one with a white safety clip, and a smaller orange one. Drivers side has 1 blue, 1 orange, and 1 white plug. Undo them all to free up the dash loom from the plug banks...

 

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There are 3 plugs hidden within the dash to get to, 1 big white one for the heater box located just behind the 'sniffer', and 2 toward the drivers side of the dash, the 'sniffer' pipe just pulls out...

 

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Now look for all the x bolts/10mm bolts holding in the dash, 2 x passenger footwell, 2 x drivers footwell, 2 x center console and 1 x 10mm nut on the upper drivers side and upper passenger side (hiding behind the vent. This parts scary as these dash's are very fragile. Use LITTLE force in an up and down motion to free the dash from its locators on the firewall, pull it gently out a little and check you've not missed any plugs.

Next remove the crash bar, but carefull, the edges are unfinished and quite sharp. 3 12mm nuts on the drivers side, 5 on the passenger side, and 2 bolting to the center console....

 

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Edited by Jezz (see edit history)
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Now, unbolt the heater box, 4 12mm bolts on top edge, and 3 10mm bolts in footwells...

 

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While R2-D2 was taking out my gas, I moved into the engine bay.

This is fiddly depending on the model of your car, charcoal can, abs etc. This sucker has both. :rolleyes: Get your pliers on the clips holding the water pipes in place, just to the top rear of the cylinder head, and pull the pipes off (sounds easy huh? :taped:) Then undo the 2 10mm bolts holding the plate in place that surrounds the pipe exit, and put it out the way..

 

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Now, onto the aircon pipes. DO NOT do this if you still have aircon gas in the system. Undo the 2 10mm bolts holding in the aircon pipes, quite fiddly if you have abs, the charcoal can can just be moved via undoing its 2 10mm bolts. Once these are undone pop the pipes out of thier sockets, and move onto the 2 10mm bolts holding the surround plate in. Once out the way, go back into the cabin and give the heater box a wiggle. Bobs you're uncle, fannys your aunt, theres the little blighter!!! Undo the 4 x screws holding the long air vent in place on top of the heater box, then undo the clamps on the water pipes and the matrix will just pull out....

 

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Edited by Jezz (see edit history)
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Nice one mate and those 2 hoses in the engine bay caused me a days delay because I couldnt get them off (cut them in the end). My system had no gas in it so I was lucky in that sense and the bolts in the engine are indeed the hardest to do!

 

My biggest tip for this is, do it in stages and put the screws in sandwich bags with labels on, it worked perfectly for me. Also label up the plugs so you know where they go if need be.

 

P.s where the hell are my hoses :D

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Putting it back together is the easy bit!!

New matrix just slots in the hole, move the pipes into place and screw up the clamps. Replace the long vent with its 4 x screws and push the heater box gently back into place, lining up the holes for the bolts top and bottom, and bolt her back in....

 

 

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Replace the crash bar, 3 12mm bolts on the drivers side, 5 12mm bolts an the passenger side...

 

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Then, (you may need an extra pair of hands here) Place the dash roughly in its position, and give it a gentle wiggle into place. You'll hear its locators pop into place along the firewall. Replace the bolt top passenger side above the vent, and the 10mm nut top drivers side near the steering columb, then move onto the lower 8 x 10mm/10mm bolts and just nip them up tight...

 

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Then plug in the white plug for the heater box, located in the dash just behing where the center dash panel will sit...

 

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And the plugs in the dash on the drivers side...

 

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Then plug in all the footwell plugs from the dash loom, 3 on each side, and dont forget the 10mm bolts each side for the dash earths. Now push the steering columb back into place, and tighten the 4 black 14mm nuts, nice and tight...

 

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Replace the handbrake and tighten the 2 17mm bolts...

 

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Then onto the gloveboxes, upper first, 2 x 8mm screws / bolts at the top and replace the covers, then the 2 x 8mm screws / bolts on the underside of the upper glovebox. Then replace the lower glovebox, 2 x screws along the top edge, and 2 10mm bolts along the bottom edge...

 

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Now replace the center console (5 screws), dash panels(7 screws) making sure to plug all the switches back in, and go over everything and double check you've not missed any plugs etc.

Now move into the engine bay and replace the water pipe surround with its 2 10mm bolts, and the 2 water pipes (may want to use new jubilees here, as the oem clips are crap). Then replace the aircon pipe surround panel with its 2 10mm bolts, and push the pipes into the sockets and tighten the 2 10mm bolts. Tight, but not over tight...

 

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Refill your rad with water and anti freeze to the correct level. Now check you have ignition, all lights, indicators, heater controls etc. Start the car. Let her go through a heat cycle first, then go over the pipes and check there's no leaks, and check all the heater controls work correctly, and it blows nice and warm when told to. Then go and get an aircon re-gas and.............Relax with a coffee and a cigarette. :D

 

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This took me 3 hours, but i'd expect a novice to take it easy over a whole day.

Hope this is of use. ;)

Edited by Jezz (see edit history)
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I guess laying in an empty royal mail depot waiting for some workshy oiyk to get his arse back to work and stop moaning about 'money and conditions'. :taped: :D

 

Ironic...I did all this to get some heat and to top it off I could still end up freezing :(

 

Great guide though mate you really do cover everything you need too. Like you say 2 people to handle the dash is a must really as it makes it much easier.

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Excellent write up Jezz, thanks very much for taking the time to do it :)

 

Do you mind if this is poached for the Tech Reference section?

 

Not at all mate. I guess i'm in a good position to document stuff like this, so i'll do a few more when some interesting jobs come along. :) I think Ian needed some suspension component piccies, so i'll do that next. ;)

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  • 3 months later...

Great guide, even though mine's fine (for now), it's a great relief to know that with the right preperation and patience it's possible for people to have a go themselves. :)

 

A quick question, would having a passenger airbag rather than an upper glove box complicate matters?

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