Jdm Blood

If this is posted already, please direct me to it, couldn't find anything. Thanks.



If you check out the image, well pretty much as you can see, the plug are connected, but these two wires(black-yellow and blue) are not. I figure out that it's for the radiator fan, but where are the other wires that it's suppose to connect? Or what other option do i have?

sanimalp

I happen to know that the radiator fan wires come from the other side of the car, so i think you are on the wrong trail.. I am 1000% sure on that.

My thought is that the black/yellow is the windsheild washer fluid pump power line, and the blue is the windshield wiper motor power line.

Apparently whoever disconnected those wires hates clean windshields.. good luck

Jdm Blood

Cool... my washer fluid pump is working, but when i touch the black wire to power, the fan goes off? are you telling me that the wiring was done wrong? sorry kinda lost.....thanks

sanimalp

hmm.. that is extremely interesting.

here is what i can tell you about how the fan should be wired. There is a thermoswitch on the back of the block that senses engine coolant temp. It has an always hot wire going into it from the fuse box under the dash, and a wire going out that is hot when the switch is sensing too high of a temp. That periodically hot wire goes through a harness on the passenger side of the car and either goes straight to the radiator fan, or if you have AC, then the AC system pressure switch and the AC on/off button can then also supply power to the cooling fan and the condenser fan, but only in a set. The cooling fan can then be turned on through either the temp switch or the combination of the AC pressure switch and the AC button.

but those wires SHOULD reside on the passenger side of the car. The only wire that is related to the coolant fan on that side of the car SHOULD be the wire coming out of the fuse box and going to the temp switch. otherwise, the wiring continues to the passenger side.

What you are holding has me stumped now. do either of those wires have voltage when the car is on or off? It doesn't make sense to me that touching the wire to a power source makes the fan go off. The only way that would work is if it is tripping a fan relay, which is also up in the front passenger side corner of the car, and would work in the opposite way i would expect the relay to work.

I'll have to look through some electrical diagrams i have when i get a chance to see if i can find a better answer.

Jdm Blood

thanks for the help, much appreciated. does anybody else know where these 2 radiator fan wires go to (blue,black/yellow)? I don't have the original wires coming out of the interior (driver's side) harness to connect it to. I want to just rig it up to the proper location so that it will work. thanks for the input!

Jdm Blood

TtT....any luck?

sanimalp

alright, so i looked at the electrical diagrams for a '91 hatch SI and also the one for the DX. What year and package model is your car originally? My guess is a '91 SI because you obviously have a resistor box.

The 91 si has a black/yellow and blue wire in plug c313, which is the plug you are holding. According to the honda manual I have, the yellow/black wire and the blue wire both go to the fast idle control solenoid valve from that plug, and the black/yellow comes from fuse #14 and also is spliced to the main relay, while the blue comes from b2 on the ECU. Why lighting up the black yellow gives power to the radiator fan, i have not a clue. it sounds like someone did an exciting wiring hackjob on your car. All i have to say is that you should buy the honda manual for your model and year of car and try and figure out what the hell they did. here is a crappy scan that explains half the story... good luck

jlicrx

sanimalp is correct - the blue and black/yellow wires are for the Fast Idle Control Valve found on the 89-91 Si (not on 88 Si) - from the picture, i would assume that the chassis harness is from the 88 Si - the 88 Si had the rectangular 6-wire connector - the 89-91 Si engine harness had a round 8-wire connector - 8-wires because of the added blue and black/yellow for the FICV which wasn't on the 88 Si - obviously, someone has installed the 88 Si 6-wire connector onto the 89-91 Si engine harness - again, sanimalp is correct, these wires should have nothing to do with the fan as all of the fan wires are in the passenger side connector - what are you touching the black wire to, that makes the fan go off? - the black/yellow power wire is spliced inside the harness to several other black/yellow wires that go to other things like the EACV, alternator, main relay, ELD, etc., however, the fan wires are not involved

Jdm Blood

ok thanks for the info ill check it asap and let you guys know on the update.

Jdm Blood

Update: My model is 88 Si Shell with 89 harness n ECU, is there a way to convert this setup?

Jdm Blood

Up Up Up...Anyone??

sanimalp

I am not sure what your question is. Convert what? Assuming those wires are going to the right locations, then all you need to do to run a 89+ setup with a fast idle control valve is to run the wires to the valve and match up the colors. there may be a couple other gotchas in the wiring, but you can probably search 88 si to 89+ si swap and see what comes up.

as far as other swaps that are obd1 or higher, you will need to buy a obd0 to obd1 conversion harness or make your own and add some wires for vtec and some o2 sensor wires, but other than that, you should be good to go on many of the easier swaps out there, if that is what you are asking.