- Dec 30, 2013
- 3,452
There's a bunch of things that keep cropping up around the Internet. Some of it pops up here, but usually is quickly corrected, however there's tons of sites where people quote certain things as fact. I'm trying to compile a list of common assumptions and the truth behind what they're talking about. Any help is appreciated.
"The oil gauge reads a nice 40 at idle but I'm having oil troubles!"
The oil gauge in the I6 does not provide an actual gauge, but a simulated readout. There is only a switch detecting oil pressure, so it's either off (0PSI) or on (reads 40PSI, but can be 12+)
"My key fob has terrible range! Why isn't the antenna on top working?"
The receiver for the key fob is actually located in your liftgate control module, in the back of the vehicle. The antenna (if present) is for OnStar.
"A4WD just turns on 4x4 when I need it, it's 2-wheel drive otherwise."
Partially true. When you turn to A4WD, two things happen. 1 - The front axle locks together. 2 - The transfer case partially engages. There is actually a clutch pack leading to the front in the transfer case, and in A4WD it moves between 5% and 100% torque as necessary.
"My 4x4 isn't working! I turn the switch, the light flashes but nothing happens, the switch must be broken!"
Not likely. If the light is flashing above your selection, that means the TCCM has received the proper position feedback from the switch and is engaging or attempting to engage your selection. If it backs off, there is likely an issue elsewhere in the system.
"That grille in the B pillar next to the driver door must be part of the OnStar system, right? Like a microphone?"
No. That grille actually contains a small fan and a temperature sensor, and is part of the automatic HVAC system, providing feedback to the controller to adjust the blend doors and fan speed. Your OnStar microphone (if equipped) is located in the overhead console, where the grille is up there.
"My A/C compressor has a mind of its own! I don't have the A/C turned on on the console but it is still running, or cycling!"
This is actually normal behavior. In some modes the compressor may turn on and off intermittently. If defrost is active, the A/C will remain running in an attempt to keep the windows from fogging. This is covered in the owner's manual for further reference.
"All my lights are going crazy on my instrument cluster! It must be bad."
Maybe, maybe not. This is also a fairly common symptom of an issue with the class 2 serial data bus. If there is a short in the data bus, or a failing module transmitting "garbage" over the line, it may be misinterpreted by other modules. This can show up as strange behavior in other parts of the vehicle, such as door controls not working, or the instrument cluster going bananas. A Tech II tool can help determine if a module is not communicating properly.
"My cruise control won't come on, or comes on and turns back off! Must be broken."
Maybe. Do you have a Check Engine light by chance? There are certain failure conditions which will disable cruise control. Cruise control is done digitally on this platform, rather than mechanical methods like the old days.
"My wheel hub makes a noise during a left turn, that means my passenger side is failing, right?"
Maybe. Convention would say yes, because that's where there's more "weight" thanks to physics during the turn. But there's been reports of it actually being the opposite, where this scenario would mean the driver's side is out. Best practice would be to replace both as a matching pair, it's a great opportunity to inspect your front brakes while you're at it.
"I accidentally locked my keys in my car again! Why didn't they do anything about this?"
They did. If the key is completely in the ignition switch, the driver door will lock, then unlock. If not, if you have OnStar you can call them for assistance. There is one more option - delayed locking. To activate, hold the driver door lock/unlock toggle in the lock position, then hit unlock twice on your key fob. This will cycle between delayed locking and "regular" locking. Test it out once - when you hit lock, it'll chime three times. Five seconds after all doors are closed, the doors lock. You can reverse this by following the same steps.
"I start my car on a cold night. The lights are dim for like ten seconds and the voltmeter reads only 11.5! Then all of a sudden everything brightens up and the gauge shoots up to 15. Is something broken?"
This is likely normal behavior. There is a system in place in the modern alternator that can actually disable it for a moment while the engine gets going and stabilizes. It then activates the alternator and that's when everything brightens up.
"The oil gauge reads a nice 40 at idle but I'm having oil troubles!"
The oil gauge in the I6 does not provide an actual gauge, but a simulated readout. There is only a switch detecting oil pressure, so it's either off (0PSI) or on (reads 40PSI, but can be 12+)
"My key fob has terrible range! Why isn't the antenna on top working?"
The receiver for the key fob is actually located in your liftgate control module, in the back of the vehicle. The antenna (if present) is for OnStar.
"A4WD just turns on 4x4 when I need it, it's 2-wheel drive otherwise."
Partially true. When you turn to A4WD, two things happen. 1 - The front axle locks together. 2 - The transfer case partially engages. There is actually a clutch pack leading to the front in the transfer case, and in A4WD it moves between 5% and 100% torque as necessary.
"My 4x4 isn't working! I turn the switch, the light flashes but nothing happens, the switch must be broken!"
Not likely. If the light is flashing above your selection, that means the TCCM has received the proper position feedback from the switch and is engaging or attempting to engage your selection. If it backs off, there is likely an issue elsewhere in the system.
"That grille in the B pillar next to the driver door must be part of the OnStar system, right? Like a microphone?"
No. That grille actually contains a small fan and a temperature sensor, and is part of the automatic HVAC system, providing feedback to the controller to adjust the blend doors and fan speed. Your OnStar microphone (if equipped) is located in the overhead console, where the grille is up there.
"My A/C compressor has a mind of its own! I don't have the A/C turned on on the console but it is still running, or cycling!"
This is actually normal behavior. In some modes the compressor may turn on and off intermittently. If defrost is active, the A/C will remain running in an attempt to keep the windows from fogging. This is covered in the owner's manual for further reference.
"All my lights are going crazy on my instrument cluster! It must be bad."
Maybe, maybe not. This is also a fairly common symptom of an issue with the class 2 serial data bus. If there is a short in the data bus, or a failing module transmitting "garbage" over the line, it may be misinterpreted by other modules. This can show up as strange behavior in other parts of the vehicle, such as door controls not working, or the instrument cluster going bananas. A Tech II tool can help determine if a module is not communicating properly.
"My cruise control won't come on, or comes on and turns back off! Must be broken."
Maybe. Do you have a Check Engine light by chance? There are certain failure conditions which will disable cruise control. Cruise control is done digitally on this platform, rather than mechanical methods like the old days.
"My wheel hub makes a noise during a left turn, that means my passenger side is failing, right?"
Maybe. Convention would say yes, because that's where there's more "weight" thanks to physics during the turn. But there's been reports of it actually being the opposite, where this scenario would mean the driver's side is out. Best practice would be to replace both as a matching pair, it's a great opportunity to inspect your front brakes while you're at it.
"I accidentally locked my keys in my car again! Why didn't they do anything about this?"
They did. If the key is completely in the ignition switch, the driver door will lock, then unlock. If not, if you have OnStar you can call them for assistance. There is one more option - delayed locking. To activate, hold the driver door lock/unlock toggle in the lock position, then hit unlock twice on your key fob. This will cycle between delayed locking and "regular" locking. Test it out once - when you hit lock, it'll chime three times. Five seconds after all doors are closed, the doors lock. You can reverse this by following the same steps.
"I start my car on a cold night. The lights are dim for like ten seconds and the voltmeter reads only 11.5! Then all of a sudden everything brightens up and the gauge shoots up to 15. Is something broken?"
This is likely normal behavior. There is a system in place in the modern alternator that can actually disable it for a moment while the engine gets going and stabilizes. It then activates the alternator and that's when everything brightens up.