Severity High
P2043

Reductant Temperature Sensor Circuit Range/Performance

What does the P2043 code mean?

The P2043 code indicates that the reductant temperature sensor circuit in the selective catalytic reduction (SCR) system is reporting a signal that is out of the expected range or not performing correctly. This sensor monitors the temperature of the diesel exhaust fluid (DEF) to ensure proper injection into the exhaust stream. A fault can lead to incorrect DEF dosing, potentially causing increased emissions and triggering the check engine light.

High
Severity
$50-$150
Typical Cost
High
Frequency

01. Most Common Causes

02. Symptoms You Will Notice

03. Step-by-Step Diagnosis

1

Step 1: Use an OBD2 scanner to confirm the P2043 code and check for any related codes.

2

Step 2: Visually inspect the reductant temperature sensor and its wiring for damage, corrosion, or loose connections.

3

Step 3: Test the sensor's resistance and voltage using a multimeter and compare to manufacturer specifications.

4

Step 4: If the sensor is faulty, replace it; if wiring issues are found, repair as necessary.

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04. Commonly Affected Makes

ToyotaVolkswagen FordChevrolet HondaHyundai / Kia NissanBMW

05. Frequently Asked Questions

Is it safe to drive with this code?

It is generally not recommended to drive long distances with this code, as it can lead to improper DEF dosing and increased emissions, potentially causing damage to the SCR system or triggering limp mode.

How much does it cost to fix?

The cost to fix a P2043 code typically ranges from $50 to $150, including parts and labor, depending on the specific vehicle and whether the sensor or wiring needs replacement.

06. Related Codes