P0030low severityPowertrain
HO2S Heater Control Circuit Bank 1 Sensor 1
on 2001 BMW 530i 3.0L I6 M54 · RWD
What this code means
The PCM detected a malfunction in the heater circuit of the upstream heated oxygen sensor (Bank 1, Sensor 1).
Symptoms
- Check Engine Light
- Poor fuel economy
- Longer warmup emissions
- Failed emissions test
Common causes
- Faulty O2 sensor heater
- Blown fuse
- Wiring issue
- PCM heater driver failure
Diagnostic steps
- Check O2 sensor heater fuse
- Test heater circuit resistance (should be 2-30 ohms)
- Inspect wiring to sensor
- Check PCM heater control output
Repair notes
Replace O2 sensor if heater resistance is out of spec. Check fuse and wiring first.
🔌 Don't have a code reader?
Any of these will read and clear this code — pick by how deep you want to go.
Bluetooth code reader (~$25)
Veepeak OBDCheck BLE →
Pairs with your phone — reads and clears codes, live data.
Serious DIY (~$100)
BlueDriver Pro →
Enhanced codes (ABS, airbag, TPMS) plus repair reports.
Shop-grade tablet (~$300+)
Autel MaxiCOM MK808S →
Bidirectional tests, service resets, all systems.
As an Amazon Associate, OLP earns from qualifying purchases — how we link. This never changes the specs we publish.
Other Powertrain codes on this vehicle
29CC
Misfire Cylinder 1
29CD
Misfire Cylinder 2
29CE
Misfire Cylinder 3
29CF
Misfire Cylinder 4
29D0
Misfire Cylinder 5
29D1
Misfire Cylinder 6
29D2
Misfire Cylinder 7
29E0
Lambda Additive/Idle Adaptation Limit, Bank 1
29E1
Lambda Additive/Idle Adaptation Limit, Bank 2
29E2
Lambda Multiplicative Part-Load Adaptation Limit, Bank 1