Interesting thread, and another interesting point on whether the circuitry actually exists. The 99-04 Jeep Grand Cherokee 4.0s with the same style PCM used an electric fan. Apparently the engineers felt it was more efficient there than a mechanical fan. Maybe it wasn’t offered on later model TJ 4.0s simply because they didn’t want to reinvent the wheel. When the 2.5 switched to a 2.4 an electric fan replaced the mechanical fan.
I would lean towards the circuitry not existing in the PCM. I have an 05 with a manual transmission and the plug for the optional automatic is void of any pins. My guess is they wanted to save pennies on unneeded parts, which adds up if you’re producing millions of PCMs across different platforms.
I have no dog in this fight, but I always like exploring deeper into things like @Steel City 06 has been doing here. I actually may test out the Ford fan mod just for fun. Carry on sir.
I would lean towards the circuitry not existing in the PCM. I have an 05 with a manual transmission and the plug for the optional automatic is void of any pins. My guess is they wanted to save pennies on unneeded parts, which adds up if you’re producing millions of PCMs across different platforms.
I have no dog in this fight, but I always like exploring deeper into things like @Steel City 06 has been doing here. I actually may test out the Ford fan mod just for fun. Carry on sir.