o2 sensors

Hi Mr. Danner. currently am working on 2004 civic hybrid, gives me p0141 and p1130 for the heater circuit performance. when checked computer is unable to ground the heaters. your opinion on wiring grounds to heaters manually. would it still give codes? by the way this car has 3 o2s 4 cylinder engine. concern is on two downstream o2s.

You CAN ground the heater manually, but it'll still set codes. The PCM monitors current flow through the heater element, and will always code if it's not in the specified range. .3 to 3.4A, in this case. Wiring manually would mean the heater current won't be flowing through PCM, just straight to ground.

Have you tried adding a substitute load to the heater control pin at the sensor and clearing the trouble codes? It's often the case that the PCM won't use an output with a trouble code present. By adding a load THEN clearing the code, you can temporarily fool the PCM into running the heater output.

Hi Mr.Tyler. please let me know that i am on a right spot on Forum for communication and asking technical questions. thanks for responding to my concern about the civic hybrid. i havnt tried another load on the heater circuit yet. but i havnt check the computer grounds yet either to confirm the grounds are fine and not missing. in the meanwhile i donot have another codes, cant assume the +/- are fine. computer is not easily accessible.

Yep, you're in the right place!

Definitely use a test light to check the heater power and control before digging out the PCM and it's grounds. You may have to clear the codes AND start the engine to get the PCM to activate the downstream O2 heater driver.