QMy wife called the other day because she could not get the transmission shifted out of Park on her 2008 Chevy Impala. The car started fine. She had it parked on a slight uphill inclined driveway. When a tow truck lifted the back of the car up so that the rear wheels were slightly above the front wheels, the transmission worked fine and has ever since. We are reminding each other never to park the car with the front end up. Any ideas?

AThe issue was most likely the parking pawl engagement in the transmission, which locks the final drive so the vehicle cannot move. With the car parked on an incline, the weight of the car 'leaning' on the parking pawl and its engagement with the final drive internal gear in the transmission created far more resistance to disengagement.

Since the car is front-wheel-drive, when the tow truck lifted the back of the car to a level position, that 'unloaded' the parking pawl and allowed easier disengagement.

To avoid this problem, fully set the parking brake before shifting the transmission into Park to prevent the weight of the vehicle from "leaning" on the parking pawl. If you're going to use the parking brake, set it each and every time you park the vehicle in order to prevent the parking brake cables from corroding and sticking in the "on" position.

QI have a question on the low-fuel light on my '98 F-150 truck. If the fuel gauge is broken, will the low-fuel light still work?

AThat depends. If the gauge in the instrument cluster itself has failed, the "low fuel" warning light may still illuminate when the tank is low on fuel. However, if the failure is in the fuel pump/sending unit inside the gas tank, I don't think the warning light will illuminate. If the gauge moves at all when you turn the key to the "on" position, it's probably OK. A more sophisticated test is to connect a special test unit to the harness connected at the fuel tank and vary the resistance in the circuit while watching the gauge. A simpler do-it-yourself test: With the gauge out of circuit apply battery voltage to the "positive" side of the gauge. The needle should move all the way to the Full or Empty position, depending on the vehicle.

QI have a 1997 and a 2004 Lincoln Town Car. When the headlights are turned on during the day the dash lights automatically dim, making it difficult or impossible to read the instrument panel. I see no need for this since there is a dimmer switch for the dash lights. I think it is a serious safety hazard. The dimmer switch does not overcome the decreased automatic illumination. Can anything be done?

AWhen the headlights are manually turned on via the headlight switch or automatically activated by the ambient light sensor, the instrument lighting automatically dims on the assumption you're driving at night where full brightness of the instrument lights would be a significant visual distraction.

On the other hand, when the DRL -- daytime running lights -- are activated by the Lighting Control Module when the key is in the "run" position, the headlight switch is in the "off" or "parking lights" position and the shift lever is not in Park, the high beams operate at a reduced voltage/illumination level and the instrument lighting remains in the daylight mode.

In either scenario, you should be able to adjust the instrument lighting to provide "readable" instruments. The instrument lighting dimmer switch should allow full voltage/illumination of the instruments when adjusted to its maximum setting.

Perhaps this rheostat in the instrument lighting dimmer control is not allowing full illumination, there's an instrument bulb out or the plastic lens over the instrument cluster is scratched and dirty.