Jeep JK 3.8 PWM Fan Upgrade Kit
For 2007–2011 Jeep Wrangler JK 3.8L
Upgrade your 2007–2011 Jeep Wrangler JK 3.8L from the factory-style fan setup to a modern PWM-controlled cooling fan system. This kit is designed to convert your JK to use a high-performance direct-fit PWM cooling fan, giving you better cooling control, quieter operation, and improved fan response compared to the original setup.
The 2007–2011 Jeep JK with the 3.8L engine did not come equipped with a PWM-style cooling fan. This upgrade changes that by providing the components needed to run a much more efficient PWM fan system.
What’s Included
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Direct-fit PWM cooling fan
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EZcanbus PWM fan control module
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PWM fan power harness
How It Works
This kit uses our EZcanbus PWM fan controller to operate the fan based on engine coolant temperature and A/C pressure. The controller adjusts fan speed automatically, increasing or decreasing output as cooling demand changes. Instead of the fan simply turning fully on or off, PWM control allows the fan to run at the speed needed for the situation.
That means:
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Better temperature control
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Improved A/C performance at idle and low speed
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Reduced fan noise
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Less unnecessary fan load
Fan Speed Operation by Coolant Temperature
The controller commands fan speed in stages based on coolant temperature:
|
Coolant Temperature |
Fan Speed |
|
195°F / 90°C |
15% |
|
199°F / 93°C |
30% |
|
205°F / 96°C |
50% |
|
212°F / 100°C |
75% |
|
218°F / 103°C |
100% |
CAN-Based Automatic Fan Control
The controller is configured for automatic variable fan speed operation using vehicle CAN bus data. It reads:
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Engine coolant temperature
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A/C pressure
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Engine RPM
Using this information, the module determines the correct fan speed from low to high demand. When the module is powered on and the engine is running, the fan will operate at a low base speed, then increase as engine temperature or A/C pressure rises.
Optional Override Input Options
Optional override inputs are available for customers who want to manually command higher fan speeds for custom applications. These inputs can operate the fan even with the engine off, as long as the key is in the run position.
These inputs are useful for:
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Manual fan activation
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Custom A/C control strategies
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Testing fan operation
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Additional cooling after hard use
Available Input Configurations
CANBUS ONLY
Automatic variable-speed fan control only. No manual override inputs.
POSITIVE
One positive-trigger input. Applying more than 10 volts to the input commands high fan speed.
NEGATIVE
One ground-trigger input. Grounding the input commands high fan speed.
Input Trigger Types
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Positive inputs activate when input voltage is greater than 10V
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Negative inputs activate when the input is grounded
These extra inputs can be used for manual override or other custom control strategies. Special programming is available upon request. If you need a custom configuration, contact us before ordering.
Fitment Notes
2007–2011 Jeep JK 3.8L
This kit is designed specifically to convert these models to a PWM fan setup.