Table 155. The following conditions will turn the Fan ON for Illustration 65

208

TM 9-2320-312-24-2

Troubleshooting Section

Table 155

The following conditions will turn the Fan ON for Illustration 65.

Circuit

Condition that will turn the Fan ON

Coolant temperature sensor

The coolant temperature is greater than 96 C (205 F).

A diagnostic code for the coolant temperature sensor is

active.

Exhaust brake

The "Fan with Exhaust Brake ON" parameter is programmed

to "YES".

The exhaust brake is on at least two seconds.

OEM installed A/C high pressure switch

The switch circuit is open or ON.

The engine rpm is less than 2750 rpm.

The engine is cranking. The engine has been running for

two seconds or the ignition key is in the ON position and the

engine off.

Air inlet temperature sensor

The temperature in the air inlet manifold is greater than 87 C

(189 F).

The temperature in the air inlet manifold is greater than 72 C

(162 F) while the boost pressure is greater than 70 kPa

(10 psi).

OEM installed cooling fan air solenoid valve

Open solenoid circuit

Circuit breaker for the cooling fan

Tripped breaker or open circuit

Dedicated PTO on/off switch

The "PTO Configuration" is programmed.

The "PTO Activates Cooling Fan" is programmed.

There is a short circuit in the switch or the switch is ON.

g00675587

Illustration 66

This schematic represents the on/off fan with a direct solenoid connection to the ECM and the control unit for the A/C connected to the

ECM input.