Heater packed up
Discussion
quattrophenia said:
And its not a fuse. Looks like i am going to have to find that 3rd bolt on the drivers side of the dash to inspect the wiring and connections. Just hope it's not the controller unit as I hear they are not cheap. I never have found that 3rd bolt even after slipping a disc whilst upsidedown looking for the ruddy thing in the past!
Horror of horrors, you might have to take the car to a TVR specialist to get the problem diagnosed and the third bolt found. Though I would point out that I found I could raise the left hand end of the dash enough with just the two bolts undone to gain access.
The heater control box is in the dash top, at the back directly behind the heater controls. Black box, about the size of a double height fag packet, IYSWIM. The usual problem is a burnt out connection to the main feed at the 8 wire connector block. Paul Smith repairs them (he designed the things back in the day), and there is also a company down in Essex called Pythonracing.co.uk who might be worth a call if you cannot get hold of Paul.
There is also a connection under the carpet on the side wall of the car to the left of the passenger's legs that I have had fail, and of course the heater fan may have given up. But 80-90% of the ones I hear about are caused by the burnt out terminal. You can replace it or bypass it. Heater control boxes pop up on Ebay occasionally, courtesy of Douglas Valley Breakers. Buy the terminal block as well if you can.
The heater control box is in the dash top, at the back directly behind the heater controls. Black box, about the size of a double height fag packet, IYSWIM. The usual problem is a burnt out connection to the main feed at the 8 wire connector block. Paul Smith repairs them (he designed the things back in the day), and there is also a company down in Essex called Pythonracing.co.uk who might be worth a call if you cannot get hold of Paul.
There is also a connection under the carpet on the side wall of the car to the left of the passenger's legs that I have had fail, and of course the heater fan may have given up. But 80-90% of the ones I hear about are caused by the burnt out terminal. You can replace it or bypass it. Heater control boxes pop up on Ebay occasionally, courtesy of Douglas Valley Breakers. Buy the terminal block as well if you can.
Been away for a few weeks so not had chance to have a look, till today.
Out came the bible to identify which fuse controls the heater. Being the eternal optimistic TVR owner it had to be the fuse and not some expensive electrical fix! Fuse fine - BUGGER.
Will probably be a loose connection.... connections wiggled and pushed home. Not working - double BUGGER.
OK Must be the controller unit. Dash proped up and unit identified. burn mark on connectors - Tripple BUGGER.
I am assuming that the burned terminal has occurred as a result of an overload in the control unit itself. Unless anyone has another solution I will follow the advise from earlier in this thread and send it off for (hopefully) repairing.
Checked the football scores and the mighty Whites have lost - quadruple BUGGER.
Out came the bible to identify which fuse controls the heater. Being the eternal optimistic TVR owner it had to be the fuse and not some expensive electrical fix! Fuse fine - BUGGER.
Will probably be a loose connection.... connections wiggled and pushed home. Not working - double BUGGER.
OK Must be the controller unit. Dash proped up and unit identified. burn mark on connectors - Tripple BUGGER.
I am assuming that the burned terminal has occurred as a result of an overload in the control unit itself. Unless anyone has another solution I will follow the advise from earlier in this thread and send it off for (hopefully) repairing.
Checked the football scores and the mighty Whites have lost - quadruple BUGGER.
No, it's not an inadequacy in the control unit.
It's that the terminal block cannot handle the power.
Just that one terminal.
You can bypass that one terminal, I managed it and I have never used a soldering iron before.
There is a thread on here about 3-4 years ago, showing you where to solder the bypass wire on the circuit board inside the control box.
I will go have a look for it.
It's that the terminal block cannot handle the power.
Just that one terminal.
You can bypass that one terminal, I managed it and I have never used a soldering iron before.
There is a thread on here about 3-4 years ago, showing you where to solder the bypass wire on the circuit board inside the control box.
I will go have a look for it.
Funny you should say that because I could not see any obvious damage to the circuit board and the first thing I thought was what if the 2 connector parts have just burned out. I think the eternal optimist in me wained at the sight of burned electrics! I'll have a look for the fix you refer to, but can already envisaged drilling a small hole through the outer casing and connecting via an electrical connector strip so it can easily be removed/ connected in future. Many thanks.
Here you can view a new terminal for the wiring harness http://www.racetechdirect.co.uk/car-parts/electric...
Here you can view a new moulding for the wiring harness http://www.racetechdirect.co.uk/car-parts/electric...
Here you can view a new moulding for the wiring harness http://www.racetechdirect.co.uk/car-parts/electric...
I think the burnt out connector is the wire carrying the power to the heater motor - so the bypass wire just needs to be rated higher than the fuse on that circuit. Halfrauds sell little reels of cable IIRC for a couple of quid. When I did mine all those years ago I just took the control box case apart, drilled a hole to take the bypass wire, and soldered it in place.
QBee said:
I think the burnt out connector is the wire carrying the power to the heater motor ........
It's actually the other way round. The main supply goes to the heater motor (Fuse 14 on my 97) and the motor is then earthed via the control box.The burnt pin and the one next to it are the earth connections.
Steve
Steve_D said:
QBee said:
I think the burnt out connector is the wire carrying the power to the heater motor ........
It's actually the other way round. The main supply goes to the heater motor (Fuse 14 on my 97) and the motor is then earthed via the control box.The burnt pin and the one next to it are the earth connections.
Steve
Steve_D said:
It's actually the other way round. The main supply goes to the heater motor (Fuse 14 on my 97) and the motor is then earthed via the control box.
The burnt pin and the one next to it are the earth connections.
Steve
Hi Steve,The burnt pin and the one next to it are the earth connections.
Steve
Thanks for your info. When you say the other earth pin is the one next to it, do you mean the pin to the right of the burned one or the one below it?
I am a bit confused.
If I press the terminals together and run a wire to bypass the burner pin from either side of the terminal blocks, it doesn't work ( when it should do). However, if I simple run a wire from the burned pin to the pin immediately below it, the fan kicks in to life again.
Why would bypassing the pin NOT work, but connecting the 2 pins on the control unit side of the terminals work fine?
Just for future reference. As with most things TVR when someone has a problem there seems to be several others that experience the same problem at the same time.
It seems that if you have checked the obvious things like fuses and loose connectors and have identified the problem as being the fried terminal connector, It's plausible to assume the board has fried it. Pins don't just overload and melt on their own. It seems the ageing capacitors on the board have a tendency to fail and overload the terminal. (certainly did in my case anyway).
However, as mentioned above, it's definitely worth trying a quick touch up / bypass on either side of the fried pin to confirm it is the board.
I did an exchange on mine via my local indy (Thanks Ian TorqueRVT!) And a big thanks to Paul for refurbishing the life expired ones for the TVR community, the wifey might even go out for a drive with the roof off this winter now!
It seems that if you have checked the obvious things like fuses and loose connectors and have identified the problem as being the fried terminal connector, It's plausible to assume the board has fried it. Pins don't just overload and melt on their own. It seems the ageing capacitors on the board have a tendency to fail and overload the terminal. (certainly did in my case anyway).
However, as mentioned above, it's definitely worth trying a quick touch up / bypass on either side of the fried pin to confirm it is the board.
I did an exchange on mine via my local indy (Thanks Ian TorqueRVT!) And a big thanks to Paul for refurbishing the life expired ones for the TVR community, the wifey might even go out for a drive with the roof off this winter now!
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