Circuit Description

Ignition voltage is supplied directly to Fan Control (FC) relay No. 1. PCM controls relay by grounding the control circuit through an internal solid state device called the driver. The driver supplies the ground for the component being controlled. Each driver has a fault line which is monitored by the PCM. When PCM is commanding a component on, the control circuit should be low (near zero volts). When PCM is commanding a component off, the control circuit should be high (near battery voltage).

If the fault detection circuit senses a voltage other than what is expected, this DTC will set. This DTC will also set when there is a short to ground, open in circuit, or short to battery voltage is detected on control circuit and when condition is present for at least 30 seconds.