TIRE PRESSURE WARNING SYSTEM TERMINALS OF ECU

CHECK TIRE PRESSURE WARNING ECU AND RECEIVER

1. 

   *A	except RHD and w/ Light Auto Turn-off System (w/ Delay Function)
   *B	for RHD and w/ Light Auto Turn-off System (w/ Delay Function)
   *a	Front view of wire harness connector (to Tire Pressure Warning ECU and Receiver)

   Disconnect the L48*1 or L110*2 tire pressure warning ECU and receiver connector and measure the voltage or resistance on the wire harness side.

   
   

   • *1: except RHD and w/ Light Auto Turn-off System (w/ Delay Function)

   • *2: for RHD and w/ Light Auto Turn-off System (w/ Delay Function)

   Table 1. except RHD and w/ Light Auto Turn-off System (w/ Delay Function)

   Terminal No. (Symbol)	Wiring Color	Terminal Description	Condition	Specified Condition
   L48-1 (IG) - L48-12 (GND)	R - W-B	IG power source	Power switch on (IG)	10 to 16 V
   L48-7 (+B) - L48-12 (GND)	LG - W-B	Power supply (from auxiliary battery)	Always	10 to 16 V
   L48-9 (CANH) - L48-10 (CANL)	Y - W	CAN communication line	Power switch off	54 to 69 Ω
   L48-12 (GND) - Body ground	W-B - Body ground	Ground	Always	Below 1 Ω

   Table 2. for RHD and w/ Light Auto Turn-off System (w/ Delay Function)

   Terminal No. (Symbol)	Wiring Color	Terminal Description	Condition	Specified Condition
   L110-1 (IG) - L110-12 (GND)	R - W-B	IG power source	Power switch on (IG)	10 to 16 V
   L110-9 (CANH) - L110-10 (CANL)	Y - W	CAN communication line	Power switch off	54 to 69 Ω
   L110-12 (GND) - Body ground	W-B - Body ground	Ground	Always	Below 1 Ω

2. Connect the L48*1 or L110*2 tire pressure warning ECU and receiver connector.

   
   

   • *1: except RHD and w/ Light Auto Turn-off System (w/ Delay Function)

   • *2: for RHD and w/ Light Auto Turn-off System (w/ Delay Function)

3. 

   *A	except RHD and w/ Light Auto Turn-off System (w/ Delay Function)	*B	for RHD and w/ Light Auto Turn-off System (w/ Delay Function)
   *a	Component with harness connected (Tire Pressure Warning ECU and Receiver)	-	-

   Measure the voltage and resistance according to the value(s) in the table below. If the result is not as specified, the ECU may be malfunctioning.

   Tip:

   Measure the values on the wire harness side while the connector is connected.

   Table 3. except RHD and w/ Light Auto Turn-off System (w/ Delay Function)

   Terminal No. (Symbol)	Wiring Color	Terminal Description	Condition	Specified Condition
   L48-3 (CLSW) - L48-12 (GND)	W - W-B	Tire pressure warning reset switch	Power switch on (IG) Steering pad switch assembly operated, "Change tire pressure" selected on the multi-information display and "ENTER" switch (steering pad switch assembly) pressed and held	Below 1.5 V
   			Power switch on (IG) "ENTER" switch (steering pad switch assembly) off	8 to 15 V
   L48-4 (RDA) - L48-12 (GND)	GR - W-B	Output signals	Power switch on (IG)	Pulse generation (see waveform 1)
   L48-5 (PRG) - L48-12 (GND)	L - W-B	Input signals	Power switch on (IG)	Pulse generation (see waveform 1)

   Table 4. for RHD and w/ Light Auto Turn-off System (w/ Delay Function)

   Terminal No. (Symbol)	Wiring Color	Terminal Description	Condition	Specified Condition
   L110-3 (CLSW) - L110-12 (GND)	W - W-B	Tire pressure warning reset switch	Power switch on (IG) Steering pad switch assembly operated, "Change tire pressure" selected on the multi-information display and "ENTER" switch (steering pad switch assembly) pressed and held	Below 1.5 V
   			Power switch on (IG) "ENTER" switch (steering pad switch assembly) off	8 to 15 V
   L110-4 (RDA2) - L110-12 (GND)	GR - W-B	Output signals	Power switch on (IG)	Pulse generation (see waveform 1)
   L110-5 (PRG2) - L110-12 (GND)	L - W-B	Input signals	Power switch on (IG)	Pulse generation (see waveform 1)

4. 

   *a	Example
   *b	GND

   Using an oscilloscope, check waveform 1.

   Table 5. Waveform 1:

   Item	Contents
   Terminal	L48-4 (RDA) - L48-12 (GND)*1 L110-4 (RDA2) - L110-12 (GND)*2 L48-5 (PRG) - L48-12 (GND)*1 L110-5 (PRG2) - L110-12 (GND)*2
   Tool setting	5 V/DIV, 5 ms./DIV.
   Vehicle condition	Power switch on (IG)

   
   

   • *1: except RHD and w/ Light Auto Turn-off System (w/ Delay Function)

   • *2: for RHD and w/ Light Auto Turn-off System (w/ Delay Function)

   Tip:

   The waveform shown in the illustration is an example. If the tester displays a waveform that alternates between high and low, where high is a voltage that is between the IG power source voltage and a voltage 2.2 V lower than the IG power source voltage, and where low is a voltage of between 0 and 1.2 V, the ECU can be judged normal.