ariens no power

[ILENGINE]

Engineers for mechanical equipment and the automotive industry have changed their traditional electrical circuit game in recent years. Now it is not unusual to find fuses and relays in the negative circuit of many.

I recently got called to troubleshoot a Massey Ferguson farm tractor. The initial shop tech had a bad habit of throwing parts at problems with no actual diagnostics.

The problem turned out to be a 5A fuse for a main power relay ground. The other problem was it took the shop manager 3 weeks to call me after the situation got desperate and the farmer was screaming at him.

Most people never think to switch their simple test light lead over to battery positive post to verify the circuit negative side.

Most of the older techs grew up on positive side fused/positive side control. But with the integration of electronics and EFI into mower systems, there is getting to be a lot of positive side fused with ground side switched/ground side controlled systems.

Older techs grew up on points and condensor systems for spark. When the points open, or breaks the ground, you get spark. Now those "points" control the spark and timing, fuel injectors, throttle body, fuel pump, and in some cases the PTO.