How to fix Code 52/56 heater control circuit high bank 2 sensor1/2
- Thread starter chex
- Start date
Mamba man steve
Enthusiast
i have the same problem since i installed belanger exhaust, they claim no problem Ha!!!!!!!!!!
heater control circuit high would indicate either a broken wire in the car's harness, or more likely, a bad heater in one of the O2's. Bank 2 is the Passenger side, and Sensor 1 of 2 is the upstream, in the header/manifold.
Mamba Man Steve- I would check your O2's/wiring for damage. The PCM does not check the Heater Circuit directly. Instead, it checks it AFTER you drive, when the ignition is OFF. The PCM monitors the sensors as they cool. When the sensor reaches a certain voltage level, the heater is turned on, and the PCM looks for a voltage change back to a warmer range. If the O2 responds, it passes. if not, it fails. After it fails twice, a DTC is stored upon the next Key-On cycle. Headers should not impact this, so long as the sensor gets warm enough in the first place for the test to take place.
Mamba Man Steve- I would check your O2's/wiring for damage. The PCM does not check the Heater Circuit directly. Instead, it checks it AFTER you drive, when the ignition is OFF. The PCM monitors the sensors as they cool. When the sensor reaches a certain voltage level, the heater is turned on, and the PCM looks for a voltage change back to a warmer range. If the O2 responds, it passes. if not, it fails. After it fails twice, a DTC is stored upon the next Key-On cycle. Headers should not impact this, so long as the sensor gets warm enough in the first place for the test to take place.
vprtech
Enthusiast
I believe the sbec pcm's that are used on other chryco vehicles may test the heater on shut down , but the jtec ecu used on the vipers most definitely test on start up . Basically the heater test only runs if the engine coolant temp is within a few degrees of ambient temp . If those conditions are met , is sends a low current five volt feed through the sensor , and because the sensor resistance drops with temperature the voltage drops as the sensor warms up . If the voltage does not drop below about a half a volt within a specified time , a code will be set for a heater failure . Even though the o2 sensor has an internal heater , it also relies on exhaust heat to speed the process . Changing the exhaust or the placement of the sensors can cause this type of failure . There are some o2 sensors that heat faster , and there are some options with the pcm . Please let me know if I can help you with this .
- Chris
- Chris
