DESCRIPTION The main body
ECU (multiplex network body ECU) and tire pressure warning ECU and
receiver communicate by direct line. If a malfunction occurs in this
communication signal, B1247 is output by the main body ECU (multiplex
network body ECU). |
DTC No. | Detection Item |
DTC Detection Condition | Trouble Area |
Note | | B1247 |
Tire Pressure Monitor Receiver Communication Stop |
Communication
between the tire pressure warning ECU and receiver and main body ECU
(multiplex network body ECU) is interrupted for 10 seconds or more. |
- Tire pressure warning ECU and receiver
- Wire harness or connector
- Main body ECU (Multiplex network body ECU)
| This DTC is for main body ECU (multiplex network body ECU) | WIRING DIAGRAM
 CAUTION / NOTICE / HINT
NOTICE:
PROCEDURE |
1. | INSPECT TIRE PRESSURE WARNING ECU AND RECEIVER (OUTPUT WAVEFORM) |
| (a) Using an oscilloscope, check the waveform. NOTICE:
With the connector connected, check from the backside of the connector.
Standard Voltage: |
Tester Connection | Tool Setting Range |
Condition | Specified Condition | |
K11-4 (RDA) - Body ground |
5 V/DIV.5 ms./DIV. |
Power switch on (IG) |
Waveform generation | |
 |
|
*a | Component with harness connected
(Tire Pressure Warning ECU and Receiver) | |
*b | GND | | |
|
Result | Proceed to | |
Waveform is as shown in the illustration. (Waveform alternates between 10.5 V or higher and 0.5 V or less) |
A | | Waveform does not change from 10.5 V or higher |
B | | Waveform does not change from 0.5 V or less |
C |
| A |
 | REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
| B |
| REPLACE TIRE PRESSURE WARNING ECU AND RECEIVER |
|
C |
 | |
| 2. |
CHECK TERMINAL VOLTAGE (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) OUTPUT) |
(a) Disconnect the K11 tire pressure warning ECU and receiver connector.
(b) Measure the voltage according to the value(s) in the table below. Standard Voltage: |
Tester Connection | Condition |
Specified Condition | |
K11-4 (RDA) - Body ground |
Power switch on (IG) |
10.5 V or higher |
| OK |
| REPLACE TIRE PRESSURE WARNING ECU AND RECEIVER |
|
NG | |
| |
| 3. |
CHECK HARNESS AND CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) - TIRE PRESSURE WARNING ECU AND RECEIVER) |
(a) Turn the power switch off. (b) Disconnect the G34 main body ECU (multiplex network body ECU) connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance: |
Tester Connection | Condition |
Specified Condition | |
G34-10 (RDA) - K11-4 (RDA) |
Always | Below 1 Ω | |
G34-10 (RDA) or K11-4 (RDA) - Body ground |
Always | 10 kΩ or higher |
| OK |
| REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
| NG |
| REPAIR OR REPLACE HARNESS OR CONNECTOR | | 
after registration
