Very bummed. Hope someone can help.I dida simple Spark Plug change. (looks tuff, but its not) Now, after a few minutes of driving,and at full running temp the ALT. / Trans. Temp /& Brake lamps come on. I have checked everything in my power. The truck runs perfect, always has. NO check engine light.I have had the ALT. out and sent to shop for testing, the battery tested correct. I have quad checked all my work related to R&R of the intake manifold.I have the FACTORY manuels and have tried to study the wiring diagrams to find the problembut so far no luck. Jack of all, Master of none.

 

sounds like alt

 

Did you solve this issue?