my Ram 1500 DT (2019-Present) has a check engine light with code P0135

Ram 1500 DT (2019-Present)

Error Codes

1-3 hours

Time

medium

Difficulty

medium

Severity

Error Code: P0135

3 min read

498 words

Problem Statement

Learn how to diagnose and fix P0135 oxygen sensor heater circuit issues in Ram 1500 DT (2019-Present). Step-by-step guide with diagnostic procedures and repair instructions.

Error Code

P0135

Affected Component

Exhaust System

Estimated Time

1-3 hours

⚠️ Safety Warnings

Important safety information - read before proceeding

•Disconnect the battery before working on electrical systems.
•Allow the engine to cool completely before removing any components.

Symptoms

•Check engine light illuminated
•Poor fuel economy
•Rough engine idle
•Increased emissions
•Engine performance issues

Diagnostic Steps

1
Scan the vehicle with an OBD-II scanner to confirm the P0135 code and check for any additional codes.
2
Inspect the wiring and connectors leading to the upstream oxygen sensor for damage, corrosion, or poor connections.
3
Measure the resistance of the oxygen sensor heater circuit using a multimeter to determine if it is within manufacturer specifications.
4
Check the vehicle’s fuse box for any blown fuses related to the oxygen sensor circuit.
5
Test the voltage at the oxygen sensor connector while the engine is running to ensure proper power supply to the sensor heater circuit.

Solution

💡 Expert Tip

For complex repairs like this, consider taking photos at each step. This helps if you need to reverse a step or consult with a mechanic. Also, keep all removed parts organized - you may need to reference them during reassembly.

Verification

After completing the repair, verify that the issue has been resolved:

✓Test the affected component to ensure it functions correctly
✓Check for any error codes or warning lights
✓Monitor the vehicle for a few days to ensure the issue does not recur

Prevention Tips

To prevent this issue from occurring again:

•Follow the manufacturer's recommended maintenance schedule
•Address warning signs early before they develop into major issues
•Use quality parts and fluids recommended for your vehicle
•Keep detailed records of all repairs and maintenance

Tools & Equipment Required

•OBD-II scanner
•Multimeter
•Oxygen sensor socket
•Torque wrench
•Wire strippers
•Soldering iron

Parts Required

•Upstream oxygen sensor
•Anti-seize compound

Related Faults

Share this solution

Comments

No comments yet

Be the first to share your thoughts

Back to Generation

Diagnostic Steps

1
Scan the vehicle with an OBD-II scanner to confirm the P0135 code and check for any additional codes.
2
Inspect the wiring and connectors leading to the upstream oxygen sensor for damage, corrosion, or poor connections.
3
Measure the resistance of the oxygen sensor heater circuit using a multimeter to determine if it is within manufacturer specifications.
4
Check the vehicle’s fuse box for any blown fuses related to the oxygen sensor circuit.
5
Test the voltage at the oxygen sensor connector while the engine is running to ensure proper power supply to the sensor heater circuit.

Solution

1. Preparation

Gather necessary tools and parts.
Disconnect the battery to ensure safety during repair.

2. Inspect and Repair Wiring

Step 1: Visually inspect the wiring harness for the upstream oxygen sensor.
Step 2: Repair any damaged wires or connectors by soldering or using appropriate connectors.
Tools Required: Wire strippers, soldering iron, electrical tape.

3. Replace Upstream Oxygen Sensor

Step 1: Remove the old oxygen sensor using an oxygen sensor socket.
Step 2: Apply anti-seize compound to the threads of the new oxygen sensor.
Step 3: Install the new oxygen sensor and tighten it to manufacturer specifications (usually around 30 lb-ft).
Tools Required: Oxygen sensor socket, torque wrench.

4. Reconnect Battery

Step 1: Reconnect the battery terminals.
Step 2: Ensure the connections are secure and free from corrosion.

5. Clear Codes and Test

Step 1: Use the OBD-II scanner to clear the P0135 code from the vehicle’s computer.
Step 2: Start the engine and allow it to reach operating temperature while monitoring the scanner for any reoccurrence of the code.