I got this code P1642 from my car I have no idea what it means

 

I just looked in the second gen service manual and I couldn't find p1642. It skipped from 1607 to1652. Are you sure of the number? Btw 1652 is a serial bus fail to the tcm. If the code you submitted is correct, it may be a trany code which is not covered in this manual.

 

I did a mistake, the code was P1684, sorry

 

It's a common code that really means nothing. It is the battery has been disconnected within the last 50 cycles. I get this code all the time even if I haven't disconnected the battery. It could be a bit of build up on the terminal , or a bit of corrosion on the ground wire (attach point). This in itself should not trip an engine light. Do you have one?

 

oh ok, yes the battery was disconnected,
no I dont have the check engine light on,
thank you, I apreciate it

 

i was re searching on the internet n some technicians say that code can be a bad battery ,corrision on terminals , dead cell in batt.

 

Thats not true, I have the that code and its just corrossion on the Terminals, its not something too worry about it wont turn on the check engine light.

 

that code is the same thing as the old code 12 from OBD1 days. really doesn't mean much basically the battery had been disconnected or dead at some point within 255 key cycle.s