Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Radiator (Cooling) Fan Control Relay(S)
The ECU controls radiator cooling fan(s) based on vehicle speed, engine coolant temperature and A/C switch position. The following tables list correct cooling fan operation based on certain conditions. See appropriate A/C SWITCH ON or A/C SWITCH OFF table.
If cooling fan does not operate as specified, see RADIATOR (COOLING) FAN CONTROL Flow chart.
| Engine Coolant Temp. °F (°C) | Vehicle Speed MPH | Radiator Fan | |
|---|---|---|---|
| Less Than 202 (94) | 50 Or More | Off | |
| " | 49 Or Less | Low | |
| 203-210 (95-99) | N/A | Low | |
| Greater Than 212 (100) | |||
| Automatic Transmission | N/A | High | |
| Manual Transmission | N/A | Low | |
| Engine Coolant Temp. °F (°C) | Vehicle Speed MPH | Radiator Fan | |
|---|---|---|---|
| Less Than 195 (90) | N/A | Off | |
| 196-201 (91-94) | 12 Or More | Off | |
| " | 12 Or Less | Low | |
| 203-210 (95-99) | 50 Or More | Off | |
| " | 49 Or Less | Low | |
| Greater Than 212 (100) | |||
| Automatic Transmission | N/A | High | |
| Manual Transmission | N/A | Low | |
| Engine Coolant Temp. °F (°C) | Vehicle Speed MPH | (1) Radiator Fan | ||
|---|---|---|---|---|
| Less Than 202 (94) | 50 Or More | Off | ||
| " | 49 Or Less | Low | ||
| 203-210 (95-99) | N/A | Low | ||
| 212-219 (100-104) | 12 Or Less | Low | ||
| " | 12 Or More | High | ||
| Greater Than 220 (105) | N/A | High | ||
|
||||
| Engine Coolant Temp. °F (°C) | Vehicle Speed MPH | Radiator Fan |
|---|---|---|
| Less Than 202 (94) | N/A | Off |
| 203-210 (95-99) | N/A | Low |
| 212-219 (100-104) | 12 Or Less | Low |
| " | 12 Or More | High |
| Greater Than 221 (105) | N/A | High |
| Engine Coolant Temp. °F (°C) | Vehicle Speed MPH | Radiator Fan |
|---|---|---|
| Less Than 202 (94) | 50 Or More | Off |
| " | 49 Or Less | On |
| 203 (95) Or More | N/A | On |
| Engine Coolant Temp. °F (°C) | Vehicle Speed MPH | Radiator Fan |
|---|---|---|
| Less Than 202 (94) | N/A | Off |
| 203-210 (95-99) | 12 Or Less | Off |
| " | 12 Or More | On |
| Greater Than 212 (100) | N/A | On |
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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