Control Unit Circuit Test

WARNING: This page is about a different car, the 2011 Nissan Juke. However, it is still accessible from the selected car via links, so may be relevant.

System Description

When the switch is ON, the control unit lights up the lamp.

Fig 1: Control Unit Circuit Diagram Case 1

Courtesy of NISSAN MOTOR CO., U.S.A.

INPUT-OUTPUT VOLTAGE CHART

Terminal No.		Description		Condition	Value (Approx.)	In case of high resistance such as single strand (V) *
+	-	Signal name	Input/Output	Condition	Value (Approx.)	In case of high resistance such as single strand (V) *
1	Body ground	Switch	Input	Switch ON	Battery voltage	Lower than battery voltage Approx. 8 (Example)
1	Body ground	Switch	Input	Switch OFF	0 V	Approx. 0
2	Body ground	Lamp	Output	Switch ON	Battery voltage	Approx. 0 (Inoperative lamp)
2	Body ground	Lamp	Output	Switch OFF	0 V	Approx. 0
The voltage value is based on the body ground. *: If high resistance exists in the switch side circuit (caused by a single strand), terminal 1 does not detect battery voltage. Control unit does not detect the switch is ON even if the switch does not turn ON. Therefore, the control unit does not supply power to light up the lamp.

Fig 2: Control Unit Circuit Diagram Case 2

Courtesy of NISSAN MOTOR CO., U.S.A.

INPUT-OUTPUT VOLTAGE CHART

Terminal No.		Description		Condition	Value (Approx.)	In case of high resistance such as single strand (V) *
+	-	Signal name	Input/Output	Condition	Value (Approx.)	In case of high resistance such as single strand (V) *
1	Body ground	Lamp	Output	Switch ON	0 V	Battery voltage (Inoperative lamp)
1	Body ground	Lamp	Output	Switch OFF	Battery voltage	Battery voltage
2	Body ground	Switch	Input	Switch ON	0 V	Higher than 0 Approx. 4 (Example)
2	Body ground	Switch	Input	Switch OFF	5 V	Approx. 5
The voltage value is based on the body ground. *: If high resistance exists in the switch side circuit (caused by a single strand), terminal 2 does not detect Approx. 0 V. Control unit does not detect the switch is ON even if the switch does not turn ON. Therefore, the control unit does not control ground to light up the lamp.