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Sorry, but OBDII is a standard, so this makes not alot of sense as I believe all the pins used for diff OBDII communications protocls differ (except batt V and gnd).

Does the vehicle use the GM version of CANbus or one of the widely used protocols that came before? Don't remember what year CANbus became a requirement. Search CANbus on the net and you can identify it by which diag port pins are present and which are not.

Never heard of a P2001 and it's a bank 2 emissions related code, so unless you have the rare v6 Ion, I'd say that was bogus.
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P2A01 HO2S Circuit Closed Loop (CL) Performance Bank 1 Sensor 2 (PCM)

That would refer to the rear O2 sensor after the Catcon.

this was extracted from a posting for a 2007 ion but I can't imagine it changed along the way...
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DTC P2A01
Circuit Description:

Heated oxygen sensors (HO2S) are used for fuel control and post catalyst monitoring. Each HO2S compares the oxygen content of the surrounding air with the oxygen content in the exhaust stream. The HO2S must reach operating temperature to provide an accurate voltage signal. Heating elements inside the HO2S minimize the time required for the sensors to reach operating temperature. The powertrain control module (PCM) supplies the HO2S with a reference, or bias, voltage of about 450 mV. When the engine is first started the PCM operates in open loop, ignoring the HO2S voltage signal. Once the HO2S reaches operating temperature and closed loop is achieved, the HO2S generates a voltage within a range of 0–1,000 mV that fluctuates above and below bias voltage. High HO2S voltage indicates a rich exhaust stream; low HO2S voltage indicates a lean exhaust stream.

The HO2S 2 is used for catalyst monitoring. This diagnostic runs once per ignition cycle. This diagnostic consists of two tests, a passive test and an intrusive test. During the passive test, if the HO2S 2 voltage transitions below 300 mV and above 750 mV, the DTC will pass for this ignition cycle. If the DTC does not pass during the passive test, the intrusive test will begin. During the intrusive test, the control module will force the air-to-fuel ratio rich and/or lean. The control module then waits for a predicted response from the HO2S. If the HO2S voltage transitions below 300 mV and/or above 750 mV, the DTC will pass for this ignition cycle. If the control module does not receive the expected response from the HO2S, DTC P2A01 will set.

DTC Descriptor:
This diagnostic procedure supports the following DTC:

DTC P2A01 HO2S Performance Sensor 2

Conditions for Running the DTC:
DTCs P0068, P0106, P0107, P0108, P0112, P0113, P0117, P0118, P0120, P0122, P0123, P0125, P0128, P0131, P0132, P0137, P0138, P0140, P0141, P0171, P0172, P0201–P0206, P0220, P0300–P0306, P0315, P0336, P0442, P0446, P0452, P0453, P0455, P0496, P0506, P0507, P0601, P0602, P0604, P0606, P060D, P060E, P0641, P0651, P1516, P1621, P2A01, P2101, P2120, P2125, P2135, P2138, P2176 are not set.

Passive Test
•The engine is running.
•The Engine Run Time parameter is less than 12 minutes.
•DTC P2A01 runs the passive test once per drive cycle when the above conditions are met.

Intrusive Test
•The Engine Run Time parameter is more than 12 minutes.
•The ignition 1 Signal parameter is between 11–18 volts.
•The Engine Speed parameter is between 1,000–5,000 RPM.
•The Vehicle Speed parameter is between 32–128 km/h (20–80 mph).
•The Short Term FT parameter is between −20 and +20 percent.
•The Air Flow Calculated parameter is between 15–100 g/s.
•The passive test did not pass.
•The maximum number of intrusive attempts is less than 11.
•DTC P2A01 runs the intrusive test once per drive cycle when the above conditions are met for 1 second.

Conditions for Setting the DTC
•The PCM detects that the HO2S 2 did not transition below 300 mV and above 750 mV during the passive test.
•One of the following tests fail:
– The PCM detects that the HO2S 2 is more than 300 mV for 10 seconds.
– The HO2S 1 is less than 300 mV.
– The PCM detects that the HO2S 2 is less than 750 mV for 10 seconds.
– The HO2S 1 is more than 600 mV.
– DTC P2A01 sets within 13 minutes when the above conditions are met.
Action Taken When the DTC Sets•The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.

•The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC
•The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
•A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
•A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
•Clear the MIL and the DTC with a scan tool.

Test Description
The number below refers to the step number on the diagnostic table.

2. If the voltage does not change more that the specified value, the condition isbpresent.

DTC P2A01
Step
Action
Value(s)
Yes
No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module Connector End Views

1 Did you perform the Diagnostic System Check – Vehicle?
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Y Go to Step 2
N Go to Diagnostic System Check - Vehicle

2
1. Start the engine.
2. Allow the engine to reach operating temperature. Refer to Scan Tool Data List.
3. Operate the engine at 1,500 RPM for 30 seconds.
4. While observing the Heated Oxygen Sensor (HO2S) 2 Voltage parameter with a scan tool, quickly cycle the throttle from closed throttle to wide open throttle, 3 times.
Did the HO2S 2 Voltage parameter change more than the specified value? (200 mV)....

If you are getting this code with no others, either the O2 sensor itself is bad or there is an issue wit the wiring, If the code is constant and the only one present, and the SES is on solid, it is likely the rear O2 sensor itself ( or the integrated heater). If the heater was dead you should get a code for slow performance or out of range for that sensor and you're not.