Cooling fans kick on as soon as car is started and stay running after key is turned off no matter how long the vehicle has ran. the ac just quit working along with the temp gauge 2001 chevy impala

SOURCE: PO481 code Chevy IMPALA 2003

Looked it up in Chilton's, confirmed in http://www.obd-codes.com/trouble_codes/

P0481 Cooling Fan 2 Control Circuit Malfunction

Each fan will throw a different code. See 3 fans listed for your model. Here's a link for the wiring schematic: http://www.chiltonlibrary.com/content/images/WD/GM/014/WD_GM_014788.pdf


Best of luck.
Greg

SOURCE: MY 2001 CHEVY IMPALA TEMP GAUGE DOES NOT REGISTER.

Check engine light? Sounds like a bad coolant temp sensor.

SOURCE: 2002 malibu runs hot.

Sounds like you have a faulty head gasket or maybe a cracked head.This can cause overheating and the check engine light to come on.The code for the o2 sensor is probably caused by coolant getting into the exhaust system and coating the sensor.The coolant fan may work but it cannot remove enough heat from the rad to make the engine cool off.Try some engine coolant stop leak to see if it will help.This maybe only a temperary fix.Let me know if you need more.MOE

SOURCE: I HAVE A 2007 CHEVY COBALT THE CHECK ENGINE LIGHT

I had this problem with a 2007 Chevy Cobalt. I changed the coolant sensor and even though the check engine light went out I still had a reading of "---" on the coolant gauge. The problem is most likely one of three things: a low coolant level, a bad coolant sensor, or the thermostat needs to be replaced. The only other possible thing it could be is a bad BCM (Body Control Module) which in that case you would most likely be having other weird problems.

The Thermostat and the sensor are both very easy to get to and replace. Take off the engine cover by removing the oil cap and they are both to the rear of the engine on the driver's side. They are right next to each other.

Hope this helps!

Marvin

• 85242 Answers
• Posted on Oct 26, 2010

SOURCE: '08 silverado. dash board diplays, engine running

P0128 OBD-II Trouble Code Technical Description

Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)
What does that mean?

This means that the engine's PCM detected that the engine has not reached the required temperature level within a specified amount of time after starting the engine. The intent of the P0128 code is to indicate a faulty thermostat. Similar codes: P0125

In determining the engine did not reach a "normal" temperature, it takes into account the length of time the vehicle has been running, the intake air temperature (IAT) sensor reading, the engine coolant temperature (ECT) sensor reading, and the speed of the vehicle.
FB.init("dd7d9e9681341cde77587bc6a2029f6f"); OBD-Codes.com on Facebook Symptoms

You will likely not notice any drivability problems other than the MIL illumination.

Causes

A code P0128 may mean that one or more of the following has happened:

• Low engine coolant level
• Leaking or stuck open thermostat
• Faulty cooling fan (running too much)
• Faulty coolant temperature (ECT) sensor
• Faulty intake air temperature (IAT) sensor

Past experience indicates that the most likely solution is to replace the thermostat. However here are some suggestions on troubleshooting and repairing a P0128 OBD-II code:

• Verify coolant strength & level
• Verify proper cooling fan operation (check if it's running more than it should). Replace if necessary.
• Verify proper engine coolant temperature (ECT) sensor operation, replace if necessary.
• Verify proper intake air temperature (IAT) sensor operation, replace if necessary.
• If the above items check out good, replace the thermostat