Q: I have 2000 E320 Mercedes Benz and code p1491 came on with Check Engine Light.

asked by on September 14, 2016

I have 2000 E320 me recedes Benz and code p1491 came on and check engine light. I took my car to my mechanic and he said no Blockage

Check Engine Light is on Inspection $79.99 - $89.99 Get a Quote

Hey there. Your question isn’t entirely clear, but I can address the code you have listed. The P1491 code has to do with your A/C system. Specifically, the high side of the A/C is too high. This could be for a number of reasons. Most commonly it will be because the cooling fans on the condenser are not turning on. But this could be result of an over filled refrigerant in the system.

It does say there is no blockage. I assume this means there is no blockage in the system, which could cause high pressure in the high side. A blockage would also cause the low side to be very low and a few other more technical details that I won’t go into. With this information, I would first be looking at the cooling fan operation.

If you should need some more assistance with this, you may want to have another expert inspect the Check Engine Light more thoroughly in order to have the precise repairs done.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

What others are asking

Car Codes p300 through p306 go off and code p1406

Hi There, Code P1406 relates to the EGR valve as you may know. The EGR valve is a small component designed to allow the flow of exhaust gases into the intake manifold in controlled amounts. Whenever you start the engine,...

What makes a car's temperature normal at idle but hot while driving? - 2000 Chevrolet Malibu

This may be related to a few different things, such as a clogged radiator not allowing coolant to circulate properly, a thermostat that may be stuck closed not allowing coolant to flow through the motor, or potentially a bad coolant...

Brand new battery car won't start - 2000 Chrysler Concorde

Hi and thank you for contacting YourMechanic. It sounds like there is a ground to chassis problem that is draining your battery. Check your negative battery cable for corrosion and make sure that the connection points are secure and clean....

New starter and battery, damn thing still won't turn over.

Hi there. It sounds like there is either a short to power or feedback occurring in an electrical circuit. Locating the faulty circuit can be time consuming, but it can be accomplished. Look for chaffed/melted wiring and corroded connectors and...

Faulty gas gauge

The fuel tank sender resistance may be off causing either a short or open causing the gauge to either be full or empty. The trunk rear fuel pump access cover should be removed and the connection removed and the fuel...

I just had water pump replaced and I'm having issues.

Hello. It sounds like something was not reinstalled correctly. The fact that the Check Engine Light is flashing tells me that there is an engine misfire. This can be caused by a loose connection or it may be something that...

Finding a rear axle leak on a 2000 Dodge

Normally it is either the gasket that is leaking at the back or the seal is leaking on the front pinion shaft where the drive shaft goes in and spins around. If you really want to find out what it...

Soft top button light stays on after battery replacement.

Hello, Typically after performing a battery change on your Mercedes Benz, you will need to re-sync the connection between the windows, the convertible top and the computer. This will allow it to know their exact positioning, and in turn allowing...

no power to fuel pump

Hi - Check the ignition switch. You are going to have one wire from the fuel pump relay to the ignition switch. As you turn the key on, this is what powers the relay to turn on the fuel pump....

Related articles

P2009 OBD-II Trouble Code: Intake Manifold Runner Control Circuit Low Bank 1
P2009 trouble code definition P2009 is a general OBD2 diagnostic trouble code indicating a fault within the intake manifold runner control circuit....
The Best Used Cars to Buy If You're a Skier
When When summer ends, skiers start thinking about hitting the hills, and that means having to contend with winter driving conditions. Not just any vehicle is going to get the job done. We have evaluated several used ski-worthy vehicles, and...
P0556 OBD-II Trouble Code: Brake Booster Pressure Sensor Circuit Range/Performance
P0556 code means there is a problem with the brake booster pressure sensor circuit often due too shorted electrical circuitry or defective valves.