P0074low severityPowertrain
Ambient Air Temperature Sensor Circuit Intermittent
on 2020 BMW i3 Range Extender · RWD
What this code means
The ambient air temperature sensor signal is dropping in and out intermittently. This can affect HVAC and engine calculations that rely on outside temperature.
Symptoms
- Fluctuating temperature display
- Intermittent check engine light
- Erratic HVAC operation
Common causes
- Loose sensor connector
- Damaged wiring
- Faulty ambient air temp sensor
- Corroded terminals
Diagnostic steps
- Scan for intermittent fault
- Wiggle test sensor wiring
- Inspect connector and pins
- Compare live sensor data
🔌 Don't have a code reader?
Any of these will read and clear this code — pick by how deep you want to go.
Budget handheld~$40
ANCEL AD410 →
No-phone-needed handheld — reads, clears, live data, freeze frame.
✓ ANCEL official store
Serious DIY~$100
BlueDriver Pro →
Enhanced codes (ABS, airbag, TPMS) plus repair reports.
SHOP FAVORITEShop-grade tablet~$300
Autel MaxiCOM MK808S →
Bidirectional tests, service resets, all systems.
✓ Autel official store
Pro diagnostics$1,500+
Autel MaxiSys MS906 Pro →
Full-system pro platform — topology mapping, ECU coding, the works.
✓ Autel official store
As an Amazon Associate and Autel/ANCEL partner, 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