I have a prototype built that does the following:
If the ignition is on, a quick press of a switch will energise the fans for 45 seconds and then switch them off
If the ignition is on, a long press of a switch (~3 seconds) will energise the fans for 5 minutes and then switch them off
If the ignition is off, a long press of a switch will energise the coolant pump for 5 minutes and then switch off
If the ignition is switched off AND the ignition has been on for more than 5 minutes, run the coolant pump for 2 minutes and then switch off
Any change in ignition (off to on or on to off) will switch off the fans or coolant pump
Any press of the switch while the fans or coolant pump are running will turn them off
If the fans or coolant pump are running, an LED flashes to indicate that they are active.
The idea is two-fold:
Firstly, to give a manual override to the temperature sensor that drives the fans normally, just in case your heart can't take the strain of hoping the fans cut in, as the temp gauge edges ever higher....
Secondly to run the auxiliary coolant pump if the car has been running for a while to exercise the pump (have you checked yours recently?? There is a high chance it is seized
) and to run coolant through the turbo even though the car isn't hot enough to trigger the 'normal' cooling down (hang on - is that 3 reasons? Nevermind)What needs to be connected up is permanent 12v, switched 12v, ground, switch, LED and a connection into the loom to activate the fans/pump, which sounds like a lot, but most of these are conveniently available on the digital clock connector or local to whatever manner of switch and LED you decide on. The best possible solution is to find a switch to match the other switchgear and, fortunately, there is such a thing in the form of the rear window demister switch from a Senator; it is a momentary switch and has a build in LED - just the job and you can even wire up the switch illumination to come on with the lights.
So after that quick overview, I wondered if there would be any call for a kit to make up your own? It will be a kit as I'm afraid I just don't have the time to construct them. The kit will include everything EXCEPT a switch, LED and hook-up wire (pick your own, but suggestions are available
). Having sat down and been through all the parts and done a rough calculation and the parts come to around £25, assuming that there is enough interest to make the manufacture of the PCB economic.Appreciate that pictures are worth a thousand words, so I will try and upload some later - frankly one PCB looks much like another, but hey-ho.
Feedback welcome, and open to adjusting the timings for the various on and off functions as they are simple to adjust.
Thoughts?
