DTC P0058 – O₂ Sensor Heater Control Circuit High (Bank 2, Sensor 2)

✅ DTC P0058 – O2 Sensor Heater Control Circuit High (Bank 2 Sensor 2)

Meaning:
The heater circuit of the downstream O₂ sensor (Bank 2 Sensor 2) is receiving higher-than-expected voltage, usually due to short to power, wiring damage, or heater element failure.

Bank 2 = the cylinder bank without cylinder 1

Sensor 2 = post-catalytic converter oxygen sensor

🔧 Common Causes

1. Short to battery voltage (B+) in the heater circuit

2. Damaged wiring harness near exhaust heat

3. O2 sensor heater internal short

4. Corroded or damaged connector

5. ECM (rare) – driver transistor stuck ON

🧰 Step-by-Step Diagnostic Procedure

1. Visual Inspection – always first

Inspect O₂ sensor wiring from exhaust to connector.

Look for:

Melted insulation

Rubbing on exhaust

Exposed copper

Oil contamination

Loose or damaged connector pins

1.If wiring is burned → repair or replace before continuing.

2. Check Heater Circuit Resistance (Sensor side)

Unplug B2S2 connector.

Measure resistance across heater pins (usually the two same-colored wires):

Normal heater resistance:

3–20 ohms (varies by vehicle)

If resistance is very low (<1 ohm):

👉🏻 Heater shorted internally → Replace O₂ sensor

If infinite (OL):

👉🏻 Heater open → Replace O₂ sensor

3. Check for Short to Power (Harness side)

With connector still unplugged:

Turn ignition ON, engine OFF
Using a multimeter, check the heater control wire to ground.

Expected:

One wire = Battery voltage (12V supply)

Other wire = ECM-controlled ground (should NOT have 12V)

If BOTH wires show 12V →

👉🏻 Short to power in harness
→ Trace & repair wiring before ECM.

4. Check Heater Control Wire to Ground

Use continuity (ohm) test between ECM-controlled wire and ground.

If continuity = 0 ohms

👉🏻 Wire shorted to ground → repair.

5. Check ECM Driver (if wiring and sensor OK)

This is rare.

Symptoms:

ECM driver stuck ON (high voltage)

No change when commanding heater test via scanner
👉🏻ECM may need repair or replacement.

🛠 Recommended Fixes

🌟 Replace downstream O₂ sensor (B2S2) if heater resistance faulty
🌟 Repair melted wiring or insulation
🌟Repair short-to-power in harness
🌟 Clean or replace corroded connectors
🌟 ECM repair only if confirmed (last step)

🚗 After Repair

1. Clear codes

2. Perform a short road test (5–10 minutes)

3. Verify no pending or active O2 heater DTCs return

Welcome to madurai car service 💐🙏🏻.