Error Code P0489: What It Means & What To Do?

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OBD II fault code P0489 is a generic code that is defined as “Exhaust gas recirculation (EGR) system -circuit low”, or, sometimes as “Exhaust Gas Recirculation “A” Control Circuit Low”. When the PCM (Powertrain Control Module) detects a low input voltage in the control circuit of the Exhaust Recirculation Valve, it will set this code P0489. It means that the engine control module (ECM) has detected

a fault with an electrical component of the EGR system.

P0489 is a diagnostic trouble code (DTC) for "Exhaust Gas Recirculation “A” Control Circuit Low". This is a generic powertrain code, which means it covers all makes/models. These engine trouble codes refer to a failure in the EGR (exhaust gas recirculation) system. Some automakers use an EGR position sensor to monitor the EGR valve itself, and then the PCM calculates the desired EGR flow according to the percentage that the valve is opened at any given moment. If the manifold air pressure fails to coincide with the PCM calculations, a code will be stored and a service engine lamp illuminated.

When an unexpected low-voltage condition occurs in the EGR valve control circuit, the PCM will set code P0489.

What causes this problem with the Exhaust Gas Recirculation "A" Control Circuit Low?

• Blocked EGR and DPFE passages
• Faulty EGR valve
• Faulty EGR control solenoid
• Wiring issue
• Blocked MAP sensor
• Defective vacuum line
• Short to ground or battery voltage

1. EGR Valve - The function of the EGR valve is to recirculate small amounts of exhaust back into the combustion chambers of the engine in order to decrease the combustion temperature, thereby reducing the formation of smog-producing nitrogen oxides.
2. EGR Valve Gasket - It seems to be a small component but a faulty egr valve gasket can create major issues as well so replace it if you discover it faulty.
3. EGR Control Solenoid - The EGR solenoid is one of the main components of the EGR system, and any problems with it can cause the system to not function, which can be a major problem in states with strict emissions regulations.
4. MAF Sensor - The Mass Air Flow Sensor is probably the best way to measure the amount of air an engine takes in (engine load). This sensor not only measures the volume of air but also compensates for its density as well.

Once you discover any of the below mentioned issues, get your vehicle diagnosed and address that problem immediately to avoid major problems and expensive repairs.

• Decreased fuel economy
• Decreased vehicle power
• Rough running engine
• Difficulty in starting
• Darker exhaust
• Illuminated check engine light

Code P0489 is one of the potentially serious codes so it is recommended to resolve this code at earliest. However, this code may not cause any major drivability issues but due to this code your vehicle can emit harmful emissions. Following repairs and replacements might help you to resolve the code:

• Clean the clogged EGR passages
• Replace the faulty EGR valve
• Inspect the wiring and connectors carefully, repair or replace the damaged one
• Repair or replace the damaged EGR control solenoid
• Repair the broken and leaked vacuum hoses

 If you are looking for any above-mentioned replacement part to fix this code, we suggest you to visit our web as we have our shelves filled with all top quality and variety products at reasonable prices.

Easy Diagnosis of Engine Error OBD Code P0489 Steps to diagnose this trouble code P0489 are as follows:

• Start the engine if it has a rough idle, pull the plug on the EGR but if it is smoothest out the pintle is stuck in the EGR. In this case, you need to replace the EGR.
• Look closely at the wiring harness for any missing insulation or possible shorts and Look for broken wires that could cause and open circuit.
• Pull the connector off the EGR and with the key on and the engine off, probe both outer terminals for power. Make a note of which one has 12-volts and replace the connector.
• Disconnect the ground wire and start the engine.
• Probe the center terminal on the EGR connector.
• Locate the "EGR Reference Voltage" terminal on the computer. Place a pin or paper clip in the computer connector at this point to back-probe the terminal.
• If 5-volts is present the computer is good and the problem is in the harness to the EGR. If no voltage is present the computer is bad.

Common Mistakes When Diagnosing the P0489 Code

The most common mistake which usually happen while diagnosing the code P0489 is the replacement of expensive “EGR valve”, without even diagnosing it carefully. Usually the other components and circuitry are the main cause responsible for storing this code and EGR valve has nothing to do with it.

P0490 - Exhaust Gas Recirculation "A" Control Circuit High