Hondata s300 V3 fan control

Hondata model coverage & ECU application questions.
Richcruze
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Hondata s300 V3 fan control

Post by Richcruze »

Hi there I have a UK spec 1999 civic hatch with a b18c engine, I have hondata s300 V3 and I want it to control the radiator fan. My car is obd2a so I have a jumper harness to the ECU which is obd1.
UK spec harness has nothing on the A27 pin that A12 would normally connect to so I have run a wire from A12 to my fan relay to what I believe to be pin 85 the bottom right pin in the picture.
I believe I also need to run a wire from pin 87 of the relay to the positive wire direct to the fan itself
Could someone please confirm if this is correct and looking at my relay in the picture what pins are 85 and 87 thanks guys
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Spunkster
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Re: Hondata s300 V3 fan control

Post by Spunkster »

You will have to look at the factory service manual to check the wiring in question.
Richcruze
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Re: Hondata s300 V3 fan control

Post by Richcruze »

This seems to have been done alot by other people in the past I've seen your advice to them surely there's a way to tell what I need to do mate I seen the attached photo you provided to someone before what I'm most confused about is what pi s are 85 and 87 on the relay ?
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Richcruze
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Re: Hondata s300 V3 fan control

Post by Richcruze »

Could you tell me at least which pins on my relay are 85 and 87 ?
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Spunkster
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Re: Hondata s300 V3 fan control

Post by Spunkster »

I do not have that information. You will have to look at the factory service manual to get this information.
Richcruze
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Re: Hondata s300 V3 fan control

Post by Richcruze »

Ok I can work out which pins are which mate but dose your diagram apply so I wire from A12 on hondata ECU to pin 85 then 87 direct to the fan in effect bypassing the switch
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Spunkster
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Re: Hondata s300 V3 fan control

Post by Spunkster »

Nothing should be bypassed.
Richcruze
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Re: Hondata s300 V3 fan control

Post by Richcruze »

Ok but is your diagram that I posted the correct way to wire up A12 to pin 85 and then pin 87 directly to the fan to allow the hondata to be able to control it
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Spunkster
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Re: Hondata s300 V3 fan control

Post by Spunkster »

That is how it should be wired with a standard bosch relay.
Richcruze
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Re: Hondata s300 V3 fan control

Post by Richcruze »

So assuming I go to the right pins on my stock fan relay it should work the same way then
Richcruze
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Re: Hondata s300 V3 fan control

Post by Richcruze »

I know you said that's how it works with a standard bosh relay but the standard relays in Honda's are jap ones so I'm just needing to know if I go to the same pins on my stock relay will it work the same way ? Thankyou
Richcruze
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Re: Hondata s300 V3 fan control

Post by Richcruze »

??
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Spunkster
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Re: Hondata s300 V3 fan control

Post by Spunkster »

The only way you will be able to tell is to try it
Richcruze
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Re: Hondata s300 V3 fan control

Post by Richcruze »

Ok mate thanks I will
Richcruze
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Re: Hondata s300 V3 fan control

Post by Richcruze »

But hang on pin 87 is already connected to fan power by the stock wiring so the only connection I was missing was the pin 85 to ECU ??? Adding that should make it work shouldn't it ?
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