JyRO

iTrader: (3)

Guys,

My cooling fans have not been working and the car got pretty hot one time on one of my boost pattern test drives.

The first thing I did was put 12 volts to each fan. The driver's side 4 fin fan came on very smoothly on low speed. The passenger side 5 fin fan would not come on.

Next, after searching here, and finding out there is a description of the electronics of the fan control in the emissions section of the FSM, I did the first test on F-146.

In doing this test, as soon as I connected TFA and GND, with the keys in my pocket, the fans came on. However, the passenger side fan ran at low speed smoothly, and the driver's side was barely turning. I put my hand on it and stopped it, to see if just the other fan was causing a pressure differential and was inducing the driver's side fan to move. But there was power to this fan to make it move.

Out of curiosity, I put the keys in and turned the ignition ON. No difference (what I expected).

Now I expect I have a relay or wire harness problem. Tonight I will inspect the function of the relays.

If anybody else has had similar problems, and have any advice, I would like to know what you did. Thanks.

Lastly, I'm going to do the FC thermoswitch change like I've been reading about. Where can I get the FC thermoswitch?

- JyRO

DaveW

Get the FC switch from Ray Crowe at Malloy: Toll-free, 888-533-3400

Great prices, knows his stuff!

JyRO

iTrader: (3)

Alrighty then,

Checked all 4 relays. 1, 2 and 4 were OK. Number 3 was NG. But taking it apart I knew there was something going on. Looking at it, 1 of the pins looked partially pulled out, and the connector housing around that pin was melted. The vehicle side connector was melted as well. So, I'll get a new relay, no big deal. But I don't know how hard it may be to get a new body side connector. Those are spade connectors, maybe I just jam them on their respective connector and hope they hold?

- JyRO

RX7 8U

iTrader: (1)

Send PM to Adam C. He bought a new FC switch. Today I talked to him and he decided not to install it. So, he might sell it.

JyRO

iTrader: (3)

Just wanted to update the post. I bought a new relay, an FC thermoswitch, and a new thermosensor. I have decided to do my own fan mod.

My fan mod is different from the one in the stickies in that the one in the stickies causes the stock wiring to back feed and pull in (at least) one extra relay. Meaning that whatever speed the cooling system asks for, it gets the next higher speed.

My system will keep the original system as designed (except in the case of using the FC thermoswitch), and when I flip my switch in the cab, I will get high speed fan operation. Also, when the ignition is turned off, my cab switch loses ground path and the fans are shut off. Evidently my car has had the cooling system TSB and the fans will operate with the ignition off. But the switch I will use will loose ground path when the ignition is off, and the fans will shut off.

This is the safest way to do it. I.E., if I'm cruising in hot summer weather and/or in city traffic, I don't even have to consider if the coolant temps. The car will still run the fans as originally designed. But I can override that to go to high speed fan with my one switch.

The wiring is a bit complex, but I have it sketched and it works (with very little load). After finishing the wiring, I'll attack replacement of the 2 sensors.

I'll post later on here about how this worked out.

- JyRO