When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Glad to hear about the quick sellout on the 1st batch! I have an early car, but am running the late model fan setup with two fans...Presumably this would work for my car? diagnostic version? thanks
The Solid-State Cooling Fan relays are expected to be back in stock in 4 to 6 weeks. The main holdup is the enclosures that are manufactured in Germany and are basically made to order. I have asked for them to be expedited and I am told they will "make delivery asap". You can send me an email and I will put you on the backorder list to be notified as soon as they are available to order.
After more than a year of development, I finally completed the Solid-State Cooling Fan Relay for the late model 944 and 968! This relay is specifically designed for dual cooling fan equipped vehicles. I am still working on one for single fan vehicles. I made two versions of it, “Standard” and “Diagnostics.” The standard version is a direct replacement for the factory mechanical relay. The diagnostics version has buttons and LEDs to quickly verify and diagnose cooling fan functionality.
Here are pictures of the two Solid-State Cooling Fan Relays side by side:
Below are internal pictures of the new F9T Solid-State Cooling Fan Relay next to various original mechanical cooling fan relays. As you can see, the “Cooling Fan Relay” actually has several “internal relays.” Each fan has a dedicated relay for low-speed and high-speed operation. However, the earlier versions have a fifth internal “control” relay that was later replaced with numerous electronic components. The factory went through several updates to the dual fan relay with the latest version being “04.” Obviously, the F9T relay takes a more modern approach. The mechanical relays are replaced with four independent “smart” power switches. These power switches are designed to drive inductive loads such as automotive cooling fans or smaller starter motors.
just picked up one of your switches. Bought it as a spare. The original switch is operating fine, any issues/benefits with going ahead and swapping it out? It’s just unplug and plug right?
Any chance that in the near distant future you could do one of those up for an early car? Or maybe an adapter of some sort so us early car guys could use the later model unit?
just picked up one of your switches. Bought it as a spare. The original switch is operating fine, any issues/benefits with going ahead and swapping it out? It’s just unplug and plug right?
The Solid-State Fan Relay (SSFR) is a direct replacement that is plug and play, simply remove the old mechanical fan relay and plug the SSFR in its place. If you have the "Diagnostic" verion, it would be a good idea to switch the ignition to the "on" position, then use the test buttons to verify high and low speed fan operation. Make sure both fans are spinning and that you hear an increase in fan speed when transitioning from the low to high speed button. Alos, it is common for the Temp Switch's low speed contacts to fail; in this case you are relying on the high-speed fans to cool the engine as a failsafe. To check for this condition, allow the engine to warm up to when the fans first come on. Verify only the low-speed LED is illuminated then press the high-speed test button, you should hear the fans kick up to high-speed mode.
Here is a video a customer created that does a great job explaining this feature while demonstrating it in real time:
Any chance that in the near distant future you could do one of those up for an early car? Or maybe an adapter of some sort so us early car guys could use the later model unit?
This is something I intend to look into. I believe the early 944 fan relay is just a relay without any control logic build into it like the later model relay. It may not be appropriate to try to adapt the late model SSFR (Solid-State Fan Relay) to the early 944. Because of this, I may just create a direct fit replacement. I will try to get some sample enclosures and build some prototypes in the second half of this year.
08-31-2021, 06:36 PM
