I have a problem with my 1999 Dodge Dakota SLT, 4 wheel drive with the 5.2L 318. When I am sitting at idle with lights on and I put the window up or down the headlights, taillights, dash lights, and break lights will dim significantly. My alternator was bad so I had to replace it anyway and the battery is only six months old. What could be causing these lights to dim the way they do? I am hoping that someone has some answers for me, something that I could try. Here's a real kicker. About three months ago my heater blower motor started acting strange. It blows good with no noise but when I am driving and I make a right turn and right turn only the blower motor will speed. When the steering is returned to normal position the blower slows back down to normal. It does not do it turning left only to the right. I've talked to numerous people about this and no one has ever heard of a blower doing this before. Has anyone out there ever experienced this kind of problem before and if so what did you do to remedy the problem. I could really use some insight. It doesn't make my truck inoperable but it sure does drive me nuts. Thanks everyone.

 

Hi and welcome to the forums,

At idle your alternator does not put out a lot of power yet has to keep running all those accessories you mentioned, plus the fuel pump, and ignition computers. The power window motors are a fairly heavy load and will cause the lights to dim. If they get very dim, you may have some binding in the window mechanism themselves.

Don't rule out that your 14 year old truck can have some dirty connections. Grounds and connections, including the battery terminals, can corrode. Even in places you can't see, such as the battery cable to connector joints. You could measure voltage drop to check for problems.

On the blower, does the air continue to come out of where you had it selected, like in defrost or the dash vents when it speeds up? I'm wondering if it's a door problem that is causing the motor to speed up or if it's an actual electrical problem. Will it do it if you just turn the wheel, not moving? Does it happen at different speeds? You could put a volt meter on the motor to check for changes. Possibly there is some damage to the blower motor resistor that only affect things when you turn right.

 

Thank you for the response. I do know that my alternator, battery, and cables are clean and have good connections but I will check other grounds. I don't believe there is any binding in the windows though. The blower motor will speed up whether it is idling or going down the highway. It does not change when I turn the switch, it doesn't stop blowing it just blows a little harder when I turn the wheel.

 

There is one other problem that I forgot to mention about my heater blower. On occasion when I start my truck the fan won't even turn on then after I drive for a few minutes it will start blowing. I'm not certain but I feel that when I turn on the floor heat I should get more blowing out than what I do. What would reduce the amount of air that I get to the floor?