Heater Matrix

baleno20006 · February 1, 2010

Hi everyone i have just purchased a gs300 1995 im having a problem with the heaters no hot air coming through. i have got it down to that the heater matrix is no good i was woundering if anyone knows how to change it or where i can get a manual from to tell me how to do it thanks for the help Anthony.

TigerFish · February 1, 2010

How have you got to the heater matrix being the problem?

On the bulk head in the engine bay, virtually in line with the engine block, there is a cable operated valve that controls the water flow to the matrix. If it has come unclipped, or is incorrectly adjusted, you get no heat from the heater. Worth checking that out before going to the extent of replacing the matrix. You can also disconnect the pipe at that valve, and the pipe on the oposite side of the matrix pipes on the bulk head and flush the matrix out. If you are getting water flow when you flush, the chances are the matrix is fine.

baleno20006 · February 2, 2010

Hi everyone i have just purchased a gs300 1995 im having a problem with the heaters no hot air coming through. i have got it down to that the heater matrix is no good i was woundering if anyone knows how to change it or where i can get a manual from to tell me how to do it thanks for the help Anthony.

Hi thanks for the reply that valve you are talking about got changed a couple of mouths ago it seems to be working when you turn the temp up or down the cable moves the valve. im getting hot water through them two pipes but not out the other side.

TigerFish · February 3, 2010

Hi everyone i have just purchased a gs300 1995 im having a problem with the heaters no hot air coming through. i have got it down to that the heater matrix is no good i was woundering if anyone knows how to change it or where i can get a manual from to tell me how to do it thanks for the help Anthony.

Hi thanks for the reply that valve you are talking about got changed a couple of mouths ago it seems to be working when you turn the temp up or down the cable moves the valve. im getting hot water through them two pipes but not out the other side.

Yeah, mine moved the valve, but it wasn't moving it correctly, so I got cold air all the time. Which two pipes do you mean? The one going to the valve, and the other coming out of the valve? If you follow the pipe along, and into the bulkhead, you should see the return pipe from the heater coming back out the bulkhead. Is that pipe hot too? If it is, then you would seem to have coolant flow through the matrix, which would suggest a different problem. If the return pipe stays cold (which on face value would seem unlikely as you would in theory need flow through the matrix for water to flow through the valve), disconnect the in and out and try flushing the matrix. Be carefull when flushing that you don't spill water over the top of the engine, as water can end up in the plug wells and misfiring can occur, and the centre plug is a bitch to get out and requires the removal of the throttle body etc (don't ask me how I know....lol ).

You can try the self diagnostics on the heating system, just to check for fault codes if any. If you press and hold both the "Auto" and "Recirculate" buttons down while you start the car, then let go of the two buttons. It will start its diagnostics. All of the lamps will turn on and off four times. After that, codes will be displayed. Let us know what codes come up. If you get code 21 showing, this is for the solar sensor on the dash (the little smoked plastic dome on the n/s end of the dash. This can be a red herring if light levels are low, so shine a torch on it to see if 21 goes away. Any other codes let us know.

baleno20006 · February 4, 2010

Hi everyone i have just purchased a gs300 1995 im having a problem with the heaters no hot air coming through. i have got it down to that the heater matrix is no good i was woundering if anyone knows how to change it or where i can get a manual from to tell me how to do it thanks for the help Anthony.

Hi thanks for the reply that valve you are talking about got changed a couple of mouths ago it seems to be working when you turn the temp up or down the cable moves the valve. im getting hot water through them two pipes but not out the other side.

hi mate yea two pipes connecting to the valve do get hot but the pipe coming out of the bulkhead the other end stays cold im going to try at the weekend to flush the heater matrix out. is there anything else it could be.

TigerFish · February 4, 2010

Hi everyone i have just purchased a gs300 1995 im having a problem with the heaters no hot air coming through. i have got it down to that the heater matrix is no good i was woundering if anyone knows how to change it or where i can get a manual from to tell me how to do it thanks for the help Anthony.

Hi thanks for the reply that valve you are talking about got changed a couple of mouths ago it seems to be working when you turn the temp up or down the cable moves the valve. im getting hot water through them two pipes but not out the other side.

hi mate yea two pipes connecting to the valve do get hot but the pipe coming out of the bulkhead the other end stays cold im going to try at the weekend to flush the heater matrix out. is there anything else it could be.

I can't think of anything else. If one side is hot, and one side cold, it would suggest no flow. If all pipes were hot, I would of gone for the hot/cold air flow actuator but that would seem unlikely going by the symptoms so far. Do try the diagnostic check before anything else though, it may throw something up.

baleno20006 · February 4, 2010

Hi everyone i have just purchased a gs300 1995 im having a problem with the heaters no hot air coming through. i have got it down to that the heater matrix is no good i was woundering if anyone knows how to change it or where i can get a manual from to tell me how to do it thanks for the help Anthony.

Hi thanks for the reply that valve you are talking about got changed a couple of mouths ago it seems to be working when you turn the temp up or down the cable moves the valve. im getting hot water through them two pipes but not out the other side.

hi mate yea two pipes connecting to the valve do get hot but the pipe coming out of the bulkhead the other end stays cold im going to try at the weekend to flush the heater matrix out. is there anything else it could be.

hi i done the test you told me to do and i got code 21 and code 14 do you know what these are, thanks for the help

TigerFish · February 5, 2010

Hi everyone i have just purchased a gs300 1995 im having a problem with the heaters no hot air coming through. i have got it down to that the heater matrix is no good i was woundering if anyone knows how to change it or where i can get a manual from to tell me how to do it thanks for the help Anthony.

Hi thanks for the reply that valve you are talking about got changed a couple of mouths ago it seems to be working when you turn the temp up or down the cable moves the valve. im getting hot water through them two pipes but not out the other side.

hi mate yea two pipes connecting to the valve do get hot but the pipe coming out of the bulkhead the other end stays cold im going to try at the weekend to flush the heater matrix out. is there anything else it could be.

hi i done the test you told me to do and i got code 21 and code 14 do you know what these are, thanks for the help

21 is the solar sensor I mentioned above, try shining a bright torch onto it to see if 21 goes out. 14 is a short or open circuit in coolant temperature sensor circuit. If ambient air temp is below -50°c then you may get 14 showing when there is no problem.