Osirus9

iTrader: (10)

So let me start off with.. I have the FSM in front of me with the wiring diagram I need open, and I'm still confused.

This is the wiring diagram I'm using.

I need help with 2 things, and I think they're both pretty simple. Some backstory: I went and opened up my main dash harness and stripped out every wire that wasn't plugged in to something, then re-wrapped the harness and put it back in the car.

I then Installed a Haltech, so everything from the engine harness on the passenger side is gone except the wiper motor wires.

READ FROM HERE IF YOU WANT TO SKIP TO THE IMPORTANT PART

Now, when I have the car on, everything works (surprising, I know) EXCEPT I have a cooling fan warning light on, and my temperature gauge doesn't work.

Which sensor is the cooling fan warning light, and which sensor is the temperature gauge? I can see what wires they are on the back of the gauge cluster, but I don't know where they should go from there. The sensor on the bottom of the radiator is unplugged, and the sensor on the top of the filler neck is also unplugged.

I'm going to have to run new wires since the old ones are gone so all I need to know is what sensor plugs into what wire on the gauge cluster.

Many thanks in advance, and pictures would be amazingly helpful!

HOZZMANRX7

iTrader: (43)

So, it sounds like your running either an automatic or a TII since they're the only ones with electirc cooling fans stock. Pull the passenger side plastic panel between the bumper and radiator, you'll see the fan and the plug to it.

Temp gauge sending unit is behind the thermostate housing.

Just follow the wiring from those connections toward the firewall and you should find where it was separated.

satch

iTrader: (1)

There are two harness plugs that connect to the gauge cluster. These are ME-01 and ME-02. The wires from both these meter harnesses converge and lead to a connector behind the gauge unit know as FME-01. The side of the connector closest to the gauge unit is the Meter side and the Yellow/White wire from the Temp gauge connects to this plug. The Y/W wire is located in the bottom row and the fourth position from the right basically between the Red/Green (5th from the right) and the Green/Black wire (3rd from the right).

Looking at ME-01 and ME-02 again the one on the left is ME-01 and this has a Black/Red wire (Cooling Fan Indicator) and this leads to the same connector behind the dash as mentioned above. The B/R wire is located on the bottom row far left position of the Meter side (closest to the gauges) of FME-01.

Osirus9

iTrader: (10)

Thanks guys, but I'm not sure you're answering my question.

I can see on the diagram where the wires are supposed to go on the gauge cluster ( I believe that is the FME-01). I need help figuring out where those wires are supposed to go from there.

I do indeed have an s4 TII, but it is manual. There is no electric fan in front of my radiator, the only one that was there was the one for the AC, but that's been gone for years and I never had this light on before. could it be that the wires were just shorted together or something to trick the ecu into thinking it was there?

also, my haltech is using the sensor on the back of the water pump, so can I use the one on the top of the filler neck instead?

satch

iTrader: (1)

The Y/W wire from the Temp gauge that goes to FME-01 mates w/the Yellow/Black wire on the Front harness side of the connector FME-01. From there the Y/B wire of the Front harness travels across the dash to FEM-01 which is one of the two Orange connectors located just above and to the right of the ECU. FEM-01 is larger than FEM-02 and FEM-01 has a bottom row of 8 wires (FEM-02 would have 7 wires on the bottom row and this connector mates 2 B/W wires to 2 B/Y wires). The Y/B wire of this Front harmess mates w/the Y/W wire found on the Emission side of FEM-01. From there the Y/W wire goes through the firewall and leads to the Temp sending unit.

The wires related to the Cooling Fan Control Unit run to the Control Unit located either under or behind the glove box. The Control Unit plug has 6 spaces with the following wires. B/Y, B/R, G/R, B/L and B/W. If the B/R wire has a ground on it then it will cause the idiot light to come on. You could perhaps supply voltage to this wire to see if it turns off. If it does then you know this wire is grounding out somewhere. If there is no Control Unit in the dash area then the ECU has no bearing on your problem. If you truly have no electric fan, but you have the control unit then you could unplug it and that might fix your problem unless the root cause is the grounding of the B/R wire is occuring.

Osirus9

iTrader: (10)

Ah, my thanks satch. I will try tracing that wire path this weekend.

What is the temp sending unit though? is that the sensor on the back of the water pump (the LOWER sensor that sits horizontally right by the engine block)?
as I said before, my Haltech is now using that sensor (or rather, it's using a different sensor in the same hole). I still want the stock coolant gauge to work though... so can I use the top sensor on the filler neck?

satch

iTrader: (1)

The gauge uses the sending unit that is screwed into the engine. On an NA it's located right near the Oil sending unit (driver's side and below the oil filter). On a turbo I am not sure of the location, but I would guess it is the same location.

HAILERS2

The COOING FAN CONTROL UNIT was on the right side of the passengers foot well and I belive it had ENGINE FAIL embossed on it.

It outputted a ground signal to the Warning LIght Cluster in the middle of the dash and the wire color of this gnd input to the warning unit was Black/Red. So if you pull the plug off the Warning LIgtht unit and depin the RED/BLACK wire the cooling fan warnning light should go away.

Page 50-70 of the wiring manual.

This was answered earlier but I added some more?????

Osirus9

iTrader: (10)

So if I removed my cooling fan unit... and the plug the unit used to attach to... what do I do with the wire from the idiot cluster? I don't want to splice it to a power source unless i KNOW that will work. I've had bad experiences with power-to-ground situations...

OH! the sensor on the block near the oil filter! ok, that makes more sense, so I just need a wire from there to the gauge cluster. awesome.

satch

iTrader: (1)

You would just need to tape it off as there is no need for that wire especially if the cooling fan is nonexistent. You need to disconnect the wire/plug to the control unit first to see if the light goes out. If it does not then the wire is grounded out somewhere along the length of the wire.

The Y/W wire off of the gauge that connected to FME-01 can just be ran to the sending unit in a less traveled path as the original wiring currently has it if need be.

Osirus9

iTrader: (10)

ok, so basically the wire is grounded somewhere, and I want it just attached to nothing. I will check continuity on that wire to ground and see if that's the problem.

But as I said before, I (for better or for worse) REMOVED not only the unit itself, but also the plug and all the wires that went to the plug.

plus, I'd know if I had an e-fan wouldn't I? I'd be able to see it easily through the grill? Plus I never knew the FC had any e-fan besides the one for the AC condensor, and the blower motor if you want to split hairs...

HAILERS2

From my other post: " So if you pull the plug off the Warning LIgtht unit and depin the RED/BLACK wire the cooling fan warnning light should go away."

I'm not sure how that got consrued to mean you put power to it. Got me. It's why I don't hardly post anymore. Waste of time and effort.

Osirus9

iTrader: (10)

Sorry, that's what satch posted not you. I was a bit confused since you guys are giving some conflicting info. Nonetheless I greatly appreciate your efforts to help a fellow rotorite who can't read a wiring diagram to save his life. a salute to HAILERS

j9fd3s

iTrader: (3)

if you can't figure out the mazda diagram, never buy an audi/vw!

i know this is late, but the mazda diagrams are always the same power is on top of the page and the ground is on the bottom, so if you pick your circuit and the power flows vertically down.

so for example the cooling fan light. on page 50-40, the meters page, power comes in from the top left, #1, and goes thru the light bulb, and down to the fan control unit. you flip the page, and you see the fan unit grounds that circuit.

so if you've pulled out the fan unit, that wire b/r is grounded somewhere.