Is this a CDI box? 1971 250 yamaha. Under fuel tank.

SOURCE: 83 yamaha tt600e no spark

The CDI unit on the 83 model (TT600) is located under the fuel tank and suffers from heat
exposure.The solution is to get specialist help to open up the sealed CDI unit and repair/
replace internal connections (which are readily available electronic components)
When you re-install it put some heat shielding material there to protect it and this
will be OK as repair will utilise stronger parts,I think.
Later models have the CDI unit moved to the head-stem area.

(this info from a Non-mechanic who remembers what was done to his TT in Australia, many years
ago)

SOURCE: 85 yamaha virago xv1000 are the coils & cdi igntor box interchang

YES

SOURCE: will 1989 yamaha 350 warrior cdi box match up with

i have a 89 350 warrior and i was wondering if i could adapt a 90 style cdi box to my 89

SOURCE: So I have a 1998 Yamaha r1. i wasn't getting spark to the spark plugs so i bypassed the CDI box then I was getting spark then I replaced the CDI box and still no spark the cdi box was used. so is it C

Yamaha usually have a starter relay switch off the battery positive cable check to see if its the starter relay switch

SOURCE: where is the cdi box located on a 94 yamaha blaster

I pretty sure it is in front of the handlebars under the plastic.