DTC C2179/79: Tire Pressure Monitor ECU Communication Stop [08/2013 - ]: Procedure

WARNING: This page is about a different car, the 2014 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.

CHECK HARNESS AND CONNECTOR (TIRE PRESSURE WARNING ECU AND RECEIVER - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))

Disconnect the P29 or P25 tire pressure warning ECU and receiver connector.
Disconnect the H10 main body ECU (multiplex network body ECU) connector.

Measure the resistance according to the value(s) in the table below.

Standard Resistance

FOR FMVSS138 TYPE

Tester Connection	Condition	Specified Condition
P29-5 (PRG) - H10-4 (PRG)	Always	Below 1 Ω
P29-5 (PRG) - Body ground	Always	10 kΩ or higher

FOR ECE-R64 TYPE

Tester Connection	Condition	Specified Condition
P25-5 (PRG2) - H10-4 (PRG)	Always	Below 1 Ω
P25-5 (PRG2) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

REPLACE TIRE PRESSURE WARNING ECU AND RECEIVER
1. Replace the tire pressure warning ECU and receiver. Refer to REMOVAL [08/2013 - ] .
NEXT: Go to next step
CHECK DTC OUTPUT
1. Clear the DTCs. Refer to DTC CHECK / CLEAR [08/2013 - ] .
2. Turn the power switch off.
3. Turn the power switch on (IG).
4. Check for DTCs. Refer to DTC CHECK / CLEAR [08/2013 - ] .
  OK
  
  DTC C2179/79 is not output.
NG → See step 4

OK → END
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to REMOVAL [08/2013 - ]