Hi all. Got a 2000 th magna. Mate tried to install a new radio . He hooked up the rheostat wire and illumanation wire and blue wire to radio ground . He blew fuse so put bigger and better in. Had rheostat smoking. Now I don't have dash and centre console lights. Checked fuses all good. Have tailights and headlights. Any help on how to fix would be great.

Step 1: Tell your (ex)mate to f'k off!
Step 2: work out what blew.
Step 3: visit wreckers. Collect parts.
Step 4: Research how to install a radio yourself. (Keep ex-mate at a distance.)

Lol done step one. Put the radio in works fine just stuck at what blew. There is power in green white wire and black and yellow. If the rheostat is fubar would that stop the lights working

Yes, if the rheostat's cactus (and if it was smoking it's a pretty safe bet that it is), you won't have any dash illumination. There's a couple of fuses in the chain, check both the junction box (inside near driver's foot) and relay box (under bonnet) for any blown fuses. Replace with the CORRECT amperage!

Get yourself a hammer and get the following engraved deeply on the head: "Putting in a bigger fuse is NEVER the solution". Then whack your mate's forehead with the hammer real hard so every time he looks in the mirror he is reminded of this simple truth!

Cool will go to wreckers and get one. Does any one know of any wiring diagrams. One other thing I noticed was when headlights go on I lose l 2 3 on dash. Anyone know why.

D 3 2 L lights get earth via the rheostat so their brightness is controllable (along with other dash illumination) which suggests your rheostat is indeed cactus. The P R N lights earth directly via the junction box. Circuits for shift quadrant lights and rheostat below.

http://i67.tinypic.com/10hojdt.jpg

http://i65.tinypic.com/iftr8m.jpg

PS: I think you can still download the PDF manual, check this thread: http://www.aussiemagna.com/forums/showthread.php?p=1515391&page=7

Looking at the diagram b/y gets power off g/w when looked at rheostat with circuit tester headlights on b/y had volta does this mean a short

From what I can tell the rheostat sits on the earth side of all dash illumination bulbs. So having a voltage at B-Y with lights on would be correct regardless of the state of the rheostat. With ignition off and with the multitester set to measure resistance between B and B-Y you should see a variance in resistance as you move the rheostat from one end to the other. If not I'd say the rheostat's gone, if so check that you have earth at the black wire (continuity between black and the body).

Just replace the rheostat first. That's undoubtedly stuffed based on your description - and then work from there. Obviously, make sure the original wiring fault which caused the problem has been corrected first.

You better hope the rheostat fried and went open circuit before other components were damaged. There could be significant damage to wiring which you can't see.

Oh - and get a new friend.