chriscindy6369

Hope this helps you all. I have pics that show detail email me for that ok later everyone. I added this switch to mine and i can run my car at 170 if needed by running the fan.. Here's some pics to explain this better


The fan is controlled by the PCM and/or the Constant Control Relay Module (CCRM), when the EEC detects certain temperatures it will switch the fan to either it's low or high speed settings. The A/C will turn the fan to high speed when it is set to max.

But how can you bypass both the EEC and CCRM and install a manual switch to control the fan operation?

First you will have to disconnect the NEGATIVE battery terminal and locate the CCRM and a pin on its connector.

The CCRM module is located LEFT (you looking at engine) of the radiator reservoir/overfill bottle.

Now that you located the CCRM, remove the connector, you will need a 6mm socket to detach the connector from the CCRM housing.

5.0 models:

Locate PIN / WIRE #17 (GREEN with PURPLE stripe) on the connector , it should be easy to spot, the connector has numbers for each pin.



NOTES FOR 4.6L SOHC and DOHC

Hook into pin#46 on the PCM, that is located behind the passenger side kickpanel. Once you tie into that pin all you do is run it to the toggle switch, and run the other side of the switch to ground.

Next you will have to TAP a wire to #17, don't CUT THE #17 WIRE !!!, you could use a scotchlock connector to tap into it, OR REMOVE about 2 mm of insulation and wrap your wire to #17.

Get a second wire and connect it to a GOOD GROUND, now run BOTH wires into the cockpit through the firewall, choose a spot to install the SWITCH, connect the wires to each of the 2 switch terminals.

Now is test time, turn key to ON, and flip the switch......READY !!!

CONSIDERATIONS:

The fan switch will NOT change the fan operation under normal circumstances, which means that when the switch is set to OFF, normal fan behavior will be preserved.

If switched ON, the Fan will operate CONSTANTLY at HIGH SPEED no matter how is the coolant temperature or if the air Conditioning is set to ON Normal/ ON MAX.

Since the SWITCH attaches to the high speed relay negative pin in the CCRM, no HARM could be done to either the CCRM or PCM, this way the RELAY is forced to close the circuit, just as when the A/C is on the MAX position.

Adverse effects of using the FAN would be:

Reduced battery life

Increase chance of drained battery when using with faulty alternator or maybe while using hi-powered amplifiers or underdrive pulleys.

Reduced fan motor life

chriscindy6369

added attachment with pics to help

Djs94stang

Thanks for the info. I posted a while back inquiring how I could change the "on" temp for the fan since when I run in the city and below 45 mph my temp runs high because the fan turns on so late...I think it is around 220 or so. I didn't get any responses. This fix is the next best thing. The fan can be turned on when running slow to keep the engine cool.

Just curious.....how did you find all this out?

mdvaldosta

https://mustangforums.com/m_217218/m.../tm.htm#217218

96SilverLT1

I would be interested to know from anyone who has done this on a 96+ OBDII system if the switch ends up setting a ses code. I'm working on a much better manual fan switch system for the fords since no one else really has them. trouble is that I have no mustangs around here to test them on. but I think I can make a fan switch solution 1000X better while being both safe and effective. I "belive" that I can also end up making it a low and hi switch. Product development sucks.

AllVenom

I think I know the perfect button to use. I think you all know which one I'm talking about too. Yep, your traction control button. I would have to guess, and this is just a guess that the traction control button has two wires running to it. If you just wire the two wires together, this would perform the same function of pushing the switch (closes the circuit). This way you kill two birds with one stone, always disabling traction control and having a nice factory switch to turn the fan on and off.

Of course, this would just be for those of us who always disable traction control when we start the car.

AllVenom

How could this set a code if it acts in the same manner as if the a/c was on max? I would have to say that it better not set a code.

chriscindy6369

Found this on a Ford tech site