, Salem, MA

March 8, 2014

Auto Scanner: How to diagnose mystery light problem

Auto Scanner
By Larry Rubenstein

---- — Q: I own a 2002 Honda Accord, six-cylinder. The antilock braking system and traction control lights come on in the morning. We move the car back and forth and then turn off the car and turn on again, and the lights are gone. Apparently it only happens first thing in the morning. We just changed the alternator and the right front antilock braking system sensor, upper control arms with all joints and bushings. Have you heard of this problem?

A: This shouldn’t be too hard to track down. Leave the vehicle at a repair shop overnight. Before the car is started, the scanner should be put in the antilock brakes testing mode. Next, the technician sets the scanner to make a movie, which is a series of frames holding all the data. The technician will then road test the car, come back to the shop and review the data. This should end the mystery.

Q: Quick question regarding how long I should keep an open bottle of transmission fluid. On Sunday I noticed my Ford 500 was down a small amount of transmission fluid. I checked the manual to see what fluid to use, and it indicated that the correct fluid was Mercon/Dextron III fluid. So next I went to my automotive shelf in the basement to see what I had on hand and found an open bottle of trans fluid from 2004. I mark all my open bottles with the date and what vehicle they are for so that my wife or son would know what to use if they needed to add fluid to a vehicle when I was not around. My question is, should I keep the bottle of transmission fluid from 2004 or should I recycle it? I did buy a new bottle for use in my Ford 500. Is motor oil OK to use in opened containers as long as the rating is OK, or does it have a shelf life as well?

A: If you think there is a chance that moisture got into the oil, you should discard it. After nine years of being open, I don’t think I would use the transmission fluid you refer to.

Q: I have a 1998 Grand Marquis with 82,000 miles. I’ve owned the car for about three years. I noticed the coolant is a dark color, and this bothers me. I was thinking about having the system flushed. Could this possibly do any damage to the heater core? Should the thermostat be changed at the same time? Also, with this type of mileage what do you think about changing the water pump?

A: The car is very overdue for a coolant flush. You may experience coolant leaks once you do a flush. The leaks would occur if the dirt or sediment that is in your system now is blocking a leak; a flush may create that problem. Yes to the thermostat as well. There is no need to change the water pump unless it is leaking or the vehicle is not circulating the coolant.


Larry Rubenstein is a master technician who owns a North Shore service station. His column appears every Saturday. Write to Larry at The Salem News, c/o Auto Scanner, 32 Dunham Road, Beverly, MA 01915, or send an email to