FixVault
Home
›
Toyota
›
2003
›
Prius
›
Repair and Diagnosis
›
Engine Performance
›
System
›
Engine Control System Self Diagnostics
›
Diagnostic Tests
›
DTC P1637: ESTP Signal Malfunction
›
Circuit Description
Circuit Description
The Hybrid Vehicle Electronic Control Unit (HV ECU) communicates with the ECM over the ESTP circuit.