• Posted by Tucker Kuntz
• On December 21, 2017
• 0 Comments

During my almost 30 years of working on Fire Trucks the one thing I have learned that is set in stone: “As soon as you learn all the answers, someone changes all the questions.”

The trucks I worked on when I first started are light years away from the trucks produced today. Computers and NASA level electronics have replaced simple mechanical equipment. There is very little the Firefighter, Driver and sometimes even the general city shop mechanic can do if a problem arises with the newer trucks.

It is my intent here to try and post some simple things that can be done to help diagnose Issues that arise. This is not intended to promote fire fighters to work on their trucks but to help them better understand their trucks and what may or may not be causing their problem.

Not long ago I got a call from the Dept. Chief of a small-town department in North Alabama. “I’ve got a problem, the brake lights on my Pierce Saber don’t work unless I turn off the head lights. Then they work.” This started the search. Chasing an Electrical Gremlin over the phone.

My first question, “Has anyone worked on this truck?” the answer, “No, not that I Know of.”
My next question: “Not just on the lights on anything?” “No.”

After two or three calls back and forth, the problem seemed to be at the tail lights themselves. I instructed them to check the lights and sockets for posable damage or a bad socket. A few min later I got a text with Picture.
The Tail/Break light has a low watt tail and a higher watt brake. The “2” bars running left to right in the bottom of the socket should have a 2-pin bulb to match. The bulb here is a single element which was getting power from either or both sources.
Cause of Problem: Someone put in the wrong bulb.                     

 EVERYTHING AFFECTS EVERYTHING.

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