When CAN communication with ECM and BCM is impossible, IPDM E/R performs fail-safe control. After CAN communication recovers normally, it also returns to normal control.

If No CAN Communication Is Available With ECM

Control part	Fail-safe operation
Cooling fan	Outputs the pulse duty signal (PWM signal) 100% when the ignition switch is turned ON Outputs the pulse duty signal (PWM signal) 0% when the ignition switch is turned OFF
A/C compressor	A/C relay OFF
Alternator	Outputs the power generation command signal (PWM signal) 0%

If No CAN Communication Is Available With BCM

Control part

Fail-safe operation

Headlamp

Turns ON the headlamp low relay when the ignition switch is turned ON
Turns OFF the headlamp low relay when the ignition switch is turned OFF
Headlamp high relay OFF

Parking lamp
License plate lamp
Illumination
Tail lamp
Side marker lamp

Turns ON the tail lamp relay and daytime running light relay when the ignition switch is turned ON
Turns OFF the tail lamp relay and daytime running light relay when the ignition switch is turned OFF

Front wiper motor

The status just before activation of fail-safe control is maintained until the ignition switch is turned OFF while the front wiper is operating at LO or HI speed.
The wiper is operated at LO speed until the ignition switch is turned OFF if the fail-safe control is activated while the front wiper is set in the AUTO mode and the front wiper motor is operating.
Returns automatically wiper to stop position when ignition switch is turned ON if fail-safe control is activated while front wiper motor is operated and wiper stop in the other than stop position.

Front fog lamp

Front fog lamp relay OFF

Horn

Horn OFF

Ignition relay

The status just before activation of fail-safe is maintained.

Starter motor

Starter control relay OFF

Steering lock unit⁽¹⁾

Steering lock relay OFF

⁽¹⁾	For models with steering lock unit

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.

Safety Warning

Can Communication Control

Use the Manual With the Right Hardware

When to See a Mechanic

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