Jim Grant's Tech Tips
GMC Sonoma, Frustrated's Wife
is the "back-up" light switch located on a "93 GMC Sonoma?
(Standard transmission) and why is the "check gauge" light always
on and why does the water temperature gauge always say "0"?
back-up light switch is mounted on the driver's side rear of the transmission.
That's the easy part, getting at the switch on some applications can be
a vocabulary enhancer. The "check gauge" light and the non-functioning
cooler temperature gauge are likely related. Start by checking the electrical
connector at the temperature sensor. If the connector is unplugged or
corroded, the temperature gauge will not display the engine's coolant
temperature. The "check gauge" light is alerting you to the
fact that there is a problem with the readings on one of the gauges, which
may be related to the inoperative temperature gauge.