Radiator (Cooling) Fan Control
NOTE:
For radiator cooling fan relay testing, see RELAYS
under RELAYS & SOLENOIDS.
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 diagnostic chart.
A/C SWITCH ON (MAXIMA SE)
| Engine Coolant Temp. °F (°C) | Vehicle Speed MPH | Radiator Fan |
|---|---|---|
| Less Than 203 (95) | 49 Or Less | Low |
| " | 50 Or More | Off |
| 203-212 (95-100) | N/A | Low |
| 212-221 (100-105) | 12 Or Less | Low |
| " | 12 Or More | High |
| Greater Than 221 (105) | N/A | High |
A/C SWITCH OFF (MAXIMA SE)
| Engine Coolant Temp. °F (°C) | Vehicle Speed MPH | Radiator Fan |
|---|---|---|
| Less Than 203 (95) | N/A | Off |
| 203-212 (95-100) | 12 Or Less | Off |
| " | 12 Or More | Low |
| 212-221 (100-105) | 12 Or Less | Low |
| " | 12 Or More | High |
| Greater Than 221 (105) | N/A | High |
A/C SWITCH OFF
| Engine Coolant Temp. °F (°C) | Cooling Fan Speed | Relay No. (Off or On) | ||
|---|---|---|---|---|
| Less Than 205 (96) | Off | 1, 2 & 3 (Off) | ||
| Between 207-223 (97-106) | (1) Low | 1 (On); 2 & 3 (Off) | ||
| Greater Than 225 (107) | High | 1, 2 & 3 (On) | ||
|
||||
A/C SWITCH ON
| Engine Coolant Temp. °F (°C) | Cooling Fan Speed | Relay No. (Off or On) | ||||
|---|---|---|---|---|---|---|
| Less Than 201 (94) | (1) Low | 1 (On) | ||||
| Less Than 201 (94) | (1) Low | 2 & 3 (Off) | ||||
| Between 203-219 (95-104) | (2) High | 1, 2 & 3 (On) | ||||
| Greater Than 221 (105) | High | 1, 2 & 3 (On) | ||||
|
||||||
NOTE:
For diagnostic chart symbol identification, see Fig 1
.