Heater switch

[colin mee]

Hello all.just doing some small jobs.my heater switch has only ever worked on full .faulty switch ?any ideas

[phillpot]

Guessing the Wedge may be similar to the later S series where low speed is created by putting a big resistor in series with the motor feed. Could be resistor is burnt out or as simple as a broken connection or a faulty switch?

Very similar to this......................

[colin mee]

Looks like dash out job.I will try the switch. Thanks for the ohoto

[adam quantrill]

On the later wedges at you can easily swap around the connections at the fan end and check whether the fan is knackered first.

After that the switch has two rocking contacts inside, quite often the plastic melts and the contacts lose contact as it were.

You can rebuild it from a headlight switch or similar old DPDT TR7 switch if you can't get the exact fan one just keep the front from your old one to put on.

[SLB]

I've had a couple of dodgy heater switches before only working on full. Both worked fine after taking them apart and giving them a good clean, particularly the contact points which were corroded or burnt. Parts can ping about so put them on the kitchen table and take your time.

[Adrian@]

This era TVR run Lucas ballast resistors both the bolted to the chassis version and the blue/grey 1 meter long wire version (mine is looped to the outside of the wiring loom) in the engine bay (Lucas are bolted next to the engine) for speed 1 (note that they also get used for the ignition and dash dimmer too). I personally would go with the switch clean/rebuild first, using a/Castrol switch contact compound. A@

Edited by Adrian@ on Saturday 27th April 11:19

[colin mee]

I think I have a spare switch.I will try it.when the rain stops

[Adrian@]

These are very simple to clean using a 5mm strip of 2000 wet and dry (using a spray contact cleaner as the 'wetting medium') having slide the main casing off, is all that is normally required (there is not a 'need' to separate the rocker/sprung part of this switch) . A@