Overdrive not working
 

Hello, everyone.
I have a 97 Montero Sport. I love this vehicle. I am having issues with the overdrive. If I press the OD switch, I can see in the instrument panel the OD indicator turns ON/OFF. I know if the indicator is not lid, the OD is ON. if the indicator is lid "OD Off" it is obviously off. However, when the OD is active the OD never engage. Today I tried to keep the switch pressed, and... surprise!... the OD engage, but only while I keep the switch pressed. So, if the OD switch were bad, then the indicator in the instrument panel would not turn ON/OFF when I pressed it.... or.... it doesn't necessarily is the case.? Any advice will be appreciated. Thanks in advance!

Disassembly and cleaning the switch with electronic contact cleaner may solve the issue. If not, it's obvious you'll need to change that OD switch.