Hello, P0032 code on a 2005 GC 3.3, so I checked the sensor and found that the heater was open circuit. OK, replace with an NTK sensor and all was well for a few days, then the P0032 again. I checked the new sensor and found that the heater was high resistance (~400 Ohms). I didn't check before I put it in but I'm assuming it was OK (more like 2-3 Ohms). So, what's going on? Bad sensor? It was an NTK. The parts store got me a new one but I didn't want to throw it in before knowing what was happening. I was vaguely aware that the heater is supposed to be energized only while the engine is warming up, so using the harness off the old sensor, I wired up a 5 Ohm resistor and a 12V lamp on the end of a long wire to replace the burned out heater. I brought the lamp inside the van and went for a drive. The lamp lit briefly when I turned on the ignition, then went out until I started the engine. So far, so good. At least the driver in the PCM seemed ok. I drove for a half hour or so, much of it on the highway but the lamp stayed on. I assume that having heater on continuously means fried heater element.
So, after all that, my question for the techies is: how does the PCM decide to turn off the sensor heater? Coolant temp (it's normal on the dash gauge)? Intake air flow? What could cause it to leave the heater on continuously?
Thanks for your thoughts about this. Cheers, David

 

Try a genuine Chrysler part. Several techs have reported the same issue with aftermarket parts. Then replaced with Chrysler part and trouble code disappeared

 

Thanks RickMN, but the question is:why does the PCM keep the heater energized even after the engine is hot? This will presumably burn up any O2 Sensor heater, OEM or not.

 

Symptom List:
P0032-O2 SENSOR 1/1 HEATER CIRCUIT HIGH
P0038-O2 SENSOR 1/2 HEATER CIRCUIT HIGH
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be P0032-O2 SENSOR 1/1 HEATER
CIRCUIT HIGH.
When Monitored and Set Condition:
P0032-O2 SENSOR 1/1 HEATER CIRCUIT HIGH
When Monitored: Battery voltage above 10.6 volts, ASD is powered up, and O2 heater is
off.
Set Condition: Desired state does not equal Actual state. One trip fault.
P0038-O2 SENSOR 1/2 HEATER CIRCUIT HIGH
When Monitored: Battery voltage above 10.6 volts, ASD is powered up, and O2 heater is
off.
Set Condition: Desired state does not equal Actual state. One trip fault.
POSSIBLE CAUSES
O2 SENSOR HEATER OPERATION
O2 HEATER ELEMENT
O2 HEATER GROUND CIRCUIT OPEN
O2 SENSOR
O2 HEATER CONTROL SHORTED TO VOLTAGE
O2 HEATER CONTROL CIRCUIT OPEN
PCM
TEST ACTION APPLICABILITY
1 Ignition on, engine not running.
With the DRBIIIt, read DTCs and record the related Freeze Frame data.
Is the Good Trip Counter displayed and equal to zero?
All
Yes ! Go To 3
No ! Go To 2
TEST ACTION APPLICABILITY
2 Turn the ignition off.
NOTE: Allow the O2 Sensor to cool down before continuing the test. The O2
Sensor voltage should stabilize at 5.0 volts. Raising the hood may help in
reducing under hood temps quicker.
Ignition on, engine not running.
With the DRBIIIt, actuate the O2 Heater Test.
With the DRBIIIt, monitor O2 Sensor voltage for at least 2 minutes.
Does the O2 Sensor voltage stay above 4.5 volts?
All
Yes ! Go To 3
No ! Refer to the INTERMITTENT CONDITION symptom in the
Driveability category.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
3 Turn the ignition off.
NOTE: Allow the O2 sensor to cool down to room temperature.
Disconnect the O2 Sensor harness connector.
Measure the resistance across the O2 Sensor Heater element component side.
NOTE: Heater Resistance Specification: 1/1 and 2/1 = 3.0 to 4.0 ohms or 1/2
and 2/2 = 4.0 to 5.0 ohms.
Is the O2 Sensor Heater element within specification?
All
Yes ! Go To 4
No ! Replace the O2 Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
4 Turn the ignition off.
Disconnect the O2 Sensor harness connector.
Ignition on, engine not running.
With the DRBIIIt, actuate the O2 Heater Test.
Using a 12-volt test light connected to ground, probe the O2 Heater Control circuit in
the O2 Sensor harness connector.
Does the test illuminate brightly and flash on and off?
All
Yes ! Go To 5
No ! Go To 6
5 Turn the ignition off.
Disconnect the O2 Sensor harness connector.
Measure the resistance between engine ground and the O2 Heater ground circuit in
the O2 Sensor harness connector.
Is the resistance below 5.0 ohms?
All
Yes ! Replace the O2 Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No ! Repair the open in the O2 Heater ground circuit.
TEST ACTION APPLICABILITY
6 Turn the ignition off.
Disconnect the O2 Sensor harness connector.
Disconnect the PCM harness connector.
Ignition on, engine not running.
Measure the voltage on the O2 Heater Control circuit at the O2 Sensor harness
connector.
Does the voltmeter indicate any voltage present?
All
Yes ! Repair the short to voltage in the O2 Heater Control circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No ! Go To 7
7 Turn the ignition off.
Disconnect the O2 Sensor harness connector.
Disconnect the PCM harness connector.
CAUTION: DO NOT PROBE THE PCM HARNESS CONNECTORS. PROBING
THE PCM HARNESS CONNECTORS WILL DAMAGE THE PCM TERMINALS
RESULTING IN POOR TERMINAL TO PIN CONNECTION. INSTALL
MILLER SPECIAL TOOL #8815 TO PERFORM DIAGNOSIS.
Measure the resistance of the O2 Heater Control circuit from the O2 Sensor harness
connector to the appropriate terminal of special tool #8815
Is the resistance below 5.0 ohms?
All
Yes ! NOTE: Before continuing, check the PCM harness connector
terminals for corrosion, damage, or terminal push out. Repair as
necessary. Replace and program the Powertrain Control Module
in accordance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No ! Repair the open in the O2 Heater Control circuit.

 

It has a dwell % age depending on many things. It varies.

 

Thanks TNtech and MasterTech for your replies. I think I made a bad assumption when I concluded that my test lamp going off before starting the engine meant that the driver in the PCM was ok. It turns out that the 12V for the sensor heaters is fed to the PCM from the ASD relay so that is why it goes off. To check this, I removed the ASD fuse and sure enough, no heater voltage. So it looks like I have a fritzed PCM. I don't have a DRBIII so I can't do the O2 Heater Test which tests the drivers in the PCM, maybe I'll actually check with the dealer. Any thoughts?

 

If you end up replacing the PCM the dealer will need to program the vin and mileage into the controller. The DRB3 is for the dealer to verify the repair.