i got cel on my ecu,and it says that first o2 sensor heater is gone.
bought brand new oem but the problem wasnt solved.
measured all wires,tried what repair manual tells but did not found any problem.
so i think will change the ecu.
the oem ecu is 37820-prb-a05
can i use other ecu for testing?

 

U would have to get the other ecu paired to the immobilizer or else the car won't start

 

i know,but the end of part number can be different?
like a13?

 

A13 is the last numbers on a 05 type a ecu and a14 is a 06 type a ecu.

Do you have a 02-04.? Because I believe the a03-a08 is a 02-04 type a ecu. And if you have a 02-04 then you can not use a 05-06 ecu

 

There are fuses for the heater circuits in a RSX... have you checked those to make sure the circuit has power ???

Remember that when the ignition key is first turned to the On/start position, the ECU runs a sensor check. If the proper resistance is not detected, you will get a CEL for that sensor. This means that swapping to a different ECU and simply turning the key "ON" will provide the same self-test even though the vehicle will not start because of the immobilizer.

If you try another ECU, and the code immediately comes back when the key is turned on, the smart money is on the fuse. You could also still have a bad O2 sensor. Remember that the primary O2 sensor in the RSX-S is actually a WIDEBAND (A/F sensor) and the secondary sensor is the O2 sensor. This means that if you tried to use the wrong sensor, you could have damaged the ECU and/or the new sensor itself.

 

the batt voltage is at the sensor for 20seconds and than it cuts.
the sensor starts to heat.