Question

My 2002 Saturn SC2 runs fine: until it warms up. Then it loses power. Codes p0037 and p0128 appear on OBD diagnostics.

Answer 1

P0037=HO2S-12 (Bank 1 Sensor 2) Heater Circuit Low Input

 

P0128=ECT Sensor Below Thermostat Operating Range

Answer 2

P0037 SATURN - HO2S12 Heater Control Circuit Low Voltage
Read more: https://www.autocodes.com/p0037_saturn.html

P0128 SATURN - Engine Coolant Temperature Below Thermostat Regulating Temperature
Read more: https://www.autocodes.com/p0128_saturn.html