1991 Toyota Celica overdrive not working

have a trans guy look at it with age and I'm guessing high mileage it is probably worn out the overdrive clutch pak and or torque converter clutch.

Really, perhaps you didn't finish reading my question. I asked for a troubleshooting sequence.

But one thing you have to have is pressure gauges and other tools to check this out and you really should have a manual to do this as it's stuff that we can't send on anyhow.

I have to shortcut this as i'can't copy it. between tt ad E1 on check connector install voltmeter and road test it should go to 7 volts. if no voltsgo to ecu and check between L and E1 with conector installed an dshift lever in drive. if votagle exists check for defective neutral switch if no volts replace ecu if voltage from first test is 2 volts or less check for 10-14 volts on ecu at2 anc E1 in d with ignition onif 10-14 volts check for defective neutral switch if no volts ecu bad. if voltage increases form 0-7 on first test then solenoid or trans is bad if voltage is ar 0-4 volts connect voltm to OD1&E1 with connector installed on ecu check voltage with key on and switch off no volts turn switch on 10-14 volts. if not ok bad od switch or wiring.check between od1&E1 at ecu with key on should be 5 volts.if voltage is correct replace ecu if not disconnect cruise control ecuand recheck between OD1&E1 with connector installed and ignition on if it is now 5 volts replace cruise control ecu.if not check for defective cruise control wiring.celicas use 4 different transmissions and this is one of them for a celica gt so it should be in the ball park. far as I know your refund is on theway