What Does P2245 Mean?
The PCM detected abnormally low voltage in the reference voltage circuit for Bank 1 Sensor 1 oxygen sensor. This indicates the reference voltage is below the expected threshold for proper sensor operation.
Common Causes
35%
High resistance or voltage drop in O2 sensor wiring or connections
25%
Poor or corroded ground connection for O2 sensor circuit
20%
Failing oxygen sensor with internal resistance issues
12%
PCM reference voltage output below specification
8%
Damaged wiring with partial short to ground
Diagnostic Steps
1
Step 1: Measure reference voltage at O2 sensor connector with ignition on (should be approximately 0.4-0.5V)
2
Step 2: Check voltage at PCM connector to determine if voltage loss is in wiring or PCM output
3
Step 3: Measure voltage drop across positive and ground circuits while sensor is operating
4
Step 4: Inspect and clean all ground connections for O2 sensor circuit
5
Step 5: Test O2 sensor internal resistance; replace if out of specification or if wiring tests normal
Estimated Repair Cost
$150 - $500
Parts + labor, varies by vehicle and location
The PCM detected abnormally low voltage in the reference voltage circuit for Bank 1 Sensor 1 oxygen sensor. This indicates the reference voltage is below the expected threshold for proper sensor operation.
The most common cause of P2245 (O2 Sensor Reference Voltage Circuit Low Bank 1 Sensor 1) is: High resistance or voltage drop in O2 sensor wiring or connections
Typical repair costs for P2245 range from $150 to $500, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Safe to drive but fuel mixture control will be compromised, resulting in poor fuel economy and increased emissions. Engine may run rich or lean.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P2245 to identify the root cause.
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Quick Info
Category
Powertrain
System
Fuel System / Emissions Control
Difficulty
Type
Generic (SAE)
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