DTC P176A-87: Lost Communication with Fail Safe Signal (Gear Shift Control Module "A") Missing Message [08/2023 - ]: Procedure
WARNING: This page is about a different car, the 2025 Lexus RX 450h+ and 2024 Lexus RX 450h+. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK HARNESS AND CONNECTOR (SHIFT CONTROL ECU - HYBRID VEHICLE CONTROL ECU)
Pre-procedure1
- Disconnect the transmission floor shift assembly (shift control ECU) connector.
- Disconnect the hybrid vehicle control ECU connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result C35-19 (SBFS) - C59-34 (SBFS) Always Below 1 Ω Ω C35-19 (SBFS) or C59-34 (SBFS) - Body ground and other terminals Always 10 kΩ or higher kΩ Result
Proceed to OK NG
Post-procedure1
- Reconnect the hybrid vehicle control ECU connector.
- Reconnect the transmission floor shift assembly (shift control ECU) connector.
Result:
OK
REPLACE TRANSMISSION FLOOR SHIFT ASSEMBLY (SHIFT CONTROL ECU). Refer to REMOVAL [10/2022 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR