Hi guys, just been looking at the wiring diagram for the fans and just wanted to confirm or unconfirm(made up word?) what each relay does.
Relay 1 - Controls fans 1 & 2 re aircon and blower demand
Relay 2 - ECU(s) control fan 1
Relay 4 - ECU(s) control fan 2
(Basically relays 2 & 4 are controlled by the same ECUs but each fan has its own relay)
Relay 3 - When water thermoswitch comes \'on\' both fans 1 & 2 receive an extra earthing point?
I\'m confused about relay 3 as the diagram just shows the flow of electric going to another harness ground, surely the black wire on each fan permanently grounded is enough no?
Aaaah I see! Thank you, you are my hero! So that would explain my problem. If I wire my new shell the same as my donor shell (ie same coloured wires to same single relay and blank the rest off from the wierd logic based relay mash up), I should be fine?
http://www.mazdarotaryclub.com/forums/showthread.php?t=69495
I\'m assuming I have only relay 3 as I now have a v-mount, apexi power fc and no aircon therefore there would be no need for 1,2 and 4. Am I right?
Just had another look at the wiring diagram and from memory I think the 4 wires going to each fan motor are \'paired up\' i.e 2 + 2 for fan 1 and same again for fan 2.
This would mean that the black permanent ground wire for each fan is grounding the power from relay no.1 (aircon when its switched on)
Relay no.3 is grounding the power from relay no.2-ECU governed (for fan 1) and also grounding the power from relay no.4-ECU governed (for fan 2).
goldie, you are right in saying that if you no longer have aircon, relay no.1 wouldn\'t be needed. It sounds like you have one relay combining relay no.2 & no.4 which both receive the same information from the ECU anyway. Instead of having relay no.3 you might have a permanent ground instead so that when the ECU decides to turn the fans on, it doesn\'t need to go through the thermoswitch as well.
If your fans worked fine before it became a donor car, I would just do the same again if you\'re happy with how they operated. Did you get a tuner to do the fan relay deletion for you on your donor car?
Aah i see, yeah it was hayward that did the deletion during the rest of the work. So if i check the colours left in this relay and wire it that way, with the added fan wires of course, it should be fine? So there is still a signal coming from the apexi and its the thermoswitch i\'m tryin to avoid?
Had a look at the Body Electric Manual Page G-63 and the thermoswitch is part of the aircon unit. It must switch on when the aircon reaches a certain temperature and creates an extra ground when aircon requires a higher speed from the fans.I’m guessing the extra ground allows a higher current to flow through the circuit and increase the fan speed.
I would say for your one relay to work it would need:
(Info from Wiring Diagram Page B-2)
Black/Yellow wire from 15A Meter fuse in the fuse box by the drivers footwell â€" This is a switched live to your relay.
Green/Black wire from relay to connector X-05 (connector near ECU, shown on page B-1b in picture form) page Z 119 G/B(4th terminal on bottom row) â€" This is the wire that goes to your ECU (when the ECU wants your fans to come on it grounds this wire) This will then turn on the electromagnetic force which closes the switch inside your relay.
Blue wire from 60A Cooling Fan fuse in the fuse box near stock battery location â€" This is your permanent live to the relay.
Red/Yellow wire and a White wire (stock wiring red/yellow is relay no.2 going to fan 1, white is relay no.4 going to fan 2) Original wiring colours may have been used but if not, you should have 2 wires running from the same terminal on your relay with one wire going to fan 1 and the other to fan 2. This is obviously your power to the fans.
Assuming you still have stock fans, fan 1 will have one of the above power wires going to Yellow/White wire and Red/Yellow wire on that fan. Fan 2 will have the second power wire from the relay going to Yellow/White wire and a White wire on that fan.
The Black wire and Blue/Orange wire on each fan need to be grounded.
If you can trace where the wires are going to and from on your donor car’s relay, hopefully they should be similar to the above.
Wow this is brilliant help man! No i don\'t have stock fans, they\'re slim ones to accomodate the v-mount. But yeah i\'m about to strip the loom and trace it back.
No problem dude. I assume your aftermarket fans have only one positive and one negative wire, so should just be a case of grounding the negative wires and wiring each fan positive wire to each of the two power wires on your relay.
Yeah that\'s what it is! Got another slight relay problem, i\'ll post pics later but basically i have an extra relay on the passenger side of the bonnet, i\'m wondering if its to do with the fact i have the battery in the boot? Stabbing in the dark here. But it has a 30a inline fuse and a couple black n yellow thin grounds similar to the fans wired into the relay....
It wont be because of your battery being in the boot as when you relocate the battery it just needs a thick gauge cable running from the main fuse box in the stock battery location to the battery positive terminal with a fuse (120A) between the two. Then a ground wire from negative battery terminal straight to the chassis.
Best thing to do is trace the wires from the relay as you might have an aftermarket item running off this relay. Most basic relays have:
1. Switchable live wire
2. Ground wire from relay straight to chassis
3. Permanent live wire (can be taken straight from battery positive terminal, or in your case it may be taken from where the thick gauge cable connects to the main fuse box hence the relay being located near the passenger side) This permanent live wire would definitely need to be fused, which is why you have a 30A inline fuse.
4. Live wire from relay to part you are powering.
If you can trace no.2 and no.3 which should hopefully be not too bad. Then trace the other 2 wires which should explain what the relay is powering and how it is switched on and off.
Forgot to say, technically the switchable live wire should be fused as well but sometimes people don\'t as the current being drawn by the relay is very low, opposed to the permanent live wire which provides the power to the actual part and has a higher current passing through it.