Exception in rendering!

Message: window is not defined

ReferenceError: window is not defined
    at new c (/tmp/execjs20161208-83728-gqkadjjs:136:3912)
    at m.mountComponent (/tmp/execjs20161208-83728-gqkadjjs:47:15602)
    at /tmp/execjs20161208-83728-gqkadjjs:49:31860
    at a.r.perform (/tmp/execjs20161208-83728-gqkadjjs:47:12503)
    at Object.a [as renderToString] (/tmp/execjs20161208-83728-gqkadjjs:49:31821)
    at r (/tmp/execjs20161208-83728-gqkadjjs:50:21164)
    at Object.S.ReactOnRails.serverRenderReactComponent (/tmp/execjs20161208-83728-gqkadjjs:32:6073)
    at eval (eval at <anonymous> (/tmp/execjs20161208-83728-gqkadjjs:173:8), <anonymous>:10:23)
    at eval (eval at <anonymous> (/tmp/execjs20161208-83728-gqkadjjs:173:8), <anonymous>:17:3)
    at /tmp/execjs20161208-83728-gqkadjjs:173:8

P0790 OBD-II Trouble Code: Normal/Performance Switch Malfunction

check engine light

P0790 trouble code definition

A P0790 trouble code is related to a vehicle’s automatic transmission and the normal/performance switch that changes the shift points for two different driving styles.

What the P0790 code means

P0790 is an OBD-II generic powertrain code for a voltage or resistance problem with the transmission mode controller in that the signal being sent out is not within the manufacturer’s parameters. This will typically not allow the powertrain control module to allow the “power mode” that usually lets the transmission shift later and downshift earlier.

What causes the P0790 code?

Common causes for a P0790 are:

  • Faulty transmission mode switch
  • Faulty switch wiring and or connectors

What are the symptoms of the P0790 code?

A P0790 can either cause a vehicle to stay in normal mode, or the transmission could fall into “limp-mode” that limits speeds so a vehicle can make it to a repair shop with minimal damage. The overdrive light may also be illuminated.

How does a mechanic diagnose the P0790 code?

A visual inspection of the transmission mode switch will be first, paying close attention to corrosion or liquid intrusion. If wiring appears damaged, it will need to be replaced. Your mechanic will be able to test the normal/power switch itself to determine if it’s functioning properly. If not, it will need to be replaced.

Common mistakes when diagnosing the P0790 code

Some mechanics have reported finding switches that are not so much damaged as corroded. These can be cleaned and replaced but it’s not a wise fix.

How serious is the P0790 code?

It’s rare for a P0790 to cause any symptoms more serious than the inability to access the transmission’s “power mode,” so this code isn’t too serious. If a vehicle does enter limp mode however, it can be more problematic.

What repairs can fix the P0790 code?

The most common repairs for a P0790 are as follows:

  • Cleaning the transmission mode switch
  • Replacing the transmission mode switch
  • Repairing damaged wiring for the transmission mode switch

Additional comments for consideration regarding the P0790 code

Some transmission mode switches are literally a console switch that says “Normal/Power” while others are activated when the transmission is switched to sport or dynamic mode.

Need help with a P0790 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

Post a question and get free advice from our certified mechanics.

ASK A QUESTION

More related articles

Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
The Traveler’s Guide to Driving in Malaysia
CraigBurrows / Shutterstock.com Malaysia is a popular destination for many tourists today. The country has amazing sights and attractions that you will want to explore....
Veteran and Military Driver Laws and Benefits in New Mexico
The state of New Mexico offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch...


Related questions

Q: p0720 code will not stay gone

Hello. If the vehicle speed sensor has been replaced then the wiring to the sensor must be tested. If there is high resistance or any breaks in the wire then this will occur. I have also seen the signal gear...

Q: Check engine light came on and driver smelled gas

This is a known issue in many of the Audi's. An epoxy fix, as you may know, is a very tricky and somewhat of a gamble-type of fix. There is a chance it may hold for a very long time and there...

Q: Check engine light on

There area number of things that can cause a misfire such as low fuel pressure, vacuum leaks, faulty spark plugs or wires, a bad crankshaft position sensor, bad camshaft position sensor, faulty fuel injectors and many others. The most efficient...