HOW TO INSTALL POWER STROKE FUEL TEMP SOTF SWITCH
Tools You’ll Need
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10mm socket or wrench
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Trim removal tool or flathead screwdriver
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Flashlight
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Zip ties
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Drill + step bit (only if mounting a new switch hole)
Step-by-Step Installation
1. Disconnect the Batteries
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Disconnect both negative battery terminals
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This prevents CELs, shorts, or ECU damage
2. Locate the Fuel Temperature Sensor
On most Powerstrokes, the fuel temp sensor is located:
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On the high-pressure fuel rail
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Or integrated into the fuel pressure sensor harness

3. Unplug the Factory Fuel Temp Sensor
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Press the tab and unplug the factory connector
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Inspect the connector for dirt or damage
4. Install the SOTF Harness (Plug-and-Play)
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Plug the male end of the SOTF harness into the factory fuel temp sensor
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Plug the female end into the factory wiring harness
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Ensure both connectors click and lock
Do not force connectors
If it doesn’t click, it’s not seated correctly
5. Route the Switch Wiring Through the Firewall
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Locate an existing rubber grommet in the firewall
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Common spot: behind brake booster or steering column
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Carefully pass the switch wiring through
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Seal grommet if needed

6. Mount the SOTF Switch Inside the Cab
Common mounting locations:
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Lower dash panel
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Kick panel
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Center console
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Blank switch panel
Options
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Drill and mount clean
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Or zip-tie under dash for hidden install
7. Secure and Clean Up Wiring
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Zip-tie all wiring away from:
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Exhaust
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Steering shaft
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Pedals
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Avoid sharp edges
8. Reconnect Batteries
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Reconnect both negative terminals
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Tighten snug (don’t over-torque)
9. Verify Operation
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Key ON (engine off)
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Rotate switch and confirm positions change
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Start truck and check for:
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No CEL
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Normal idle
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No warning messages
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Do NOT switch tunes under heavy throttle
Only switch:
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At idle
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Or steady cruise (light throttle)
Important Notes (Read This)
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Fuel Temp SOTF works by altering fuel temp input to command tune changes
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This does NOT add power by itself
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You must have compatible tuning loaded
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Switching too fast or under load can cause limp mode
Quick Troubleshooting
CEL after install
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Check fuel temp sensor connection
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Make sure harness is fully seated
Truck won’t start
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Harness plugged in backwards
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Sensor connector not clicked in
Switch doesn’t change tunes
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Tuning not configured for SOTF
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Switch wiring damaged or pinched