1. Turn the ignition ON.
2. Use a voltmeter to test voltage at the ISU connector terminal D3.

Is voltage within the specified value?

11-14 V

Go to Step 3

Go to Step 2

Repair the open circuit between the ISU connector terminal D3 and fuse F11.

Is the repair complete?

--

System OK

--

1. Turn the ignition ON.
2. Turn the wiper switch to INT.
3. Check the voltage at the ISU connector terminal B1.

Does the voltmeter indicate a voltage within the specified value?

11-14 V

Go to Step 7

Go to Step 4

Check for an open circuit between wiper switch connector terminal C2 and ISU connector terminal B1.

Is there an open circuit?

-

Go to Step 6

Go to Step 5

Replace the wiper switch. Refer to Windshield Wiper and Washer Switch Replacement .

Is the repair complete?

--

System OK

--

Repair the open circuit between wiper switch connector terminal C2 and ISU connector terminal B1.

Is the repair complete?

--

System OK

--

1. Turn the ignition ON.
2. Turn the wiper switch to INT.
3. Check the voltage pulsing at the ISU connector terminal C3.

Does the voltmeter indicate a pulsating voltage within the specified value?

11-14 V

Go to Step 8

Go to Step 10

1. Turn the ignition ON.
2. Check the voltage at the wiper switch connector terminal A6.

Is the voltage pulsating at the specified value?

--

Go to Step 5

Go to Step 9

Repair the open circuit between the wiper switch and the wiper relay.

Is the repair complete?

--

System OK

--

Replace the ISU. Refer to Intelligent Switching Unit Replacement in Body Control System.

Is the action complete?

--

System OK

--