SUV won’t lock. What’s up with that?

I’m having trouble with my Sequoia 2002 lift gate. It won’t lock. Whether I use the remote or the internal switch. But other locks continue to work normally. I changed out the actuator mechanism and the actuator motor. But still the liftgate won’t lock. Any suggestions?I haven’t checked the Connection or the wiring. And I am not sure if the open/close switch is getting current.

Is the gate latching otherwise? (i.e. just the lock, or the latch too?).

Have you checked the Cam mechanism for the actuator to the latch? I’ve seen on locking mechanisms the cam wear down, be pushed to the side, or overall just shear (usually with debris in the door, but also from aftermarket parts not made to the proper spec).

Any pics of the assembly?

-Jim

Both the old and new mechanism latch tight. The new parts locked new and unused. I lubricated them before installing. Give me a day to get pics. But when I put the new parts together I tried my remote and internal switches but didn’t see anything move. Thought it was funny. Just not samiliar enough to fully question. I don’t know if it’s getting a current. Think I will check the connector and see if current reaches the plug when activated. Haven’t checked fuses. But other locks work so doubtful.

Update;
Checked all fuses related to automatic door mech. All ok. Next try to check wiring harness at rear hinge. Look for abrasions etc. and check plug with volt meter to see if current is reaching acuator.

Update, checked rear door wiring harness. It seems the new latch mechanism has a connector with two wires going in it that sense is whether the door is Locked or open. And tells the computer what to do. The new latch switch didn’t work correctly. And the old latch switch also didn’t work correctly. I’m returning the new motor switch And buy OEM.
What a fricken mess. Thanks Jim for you concern. I paid 25$ for a very Toyota mechanic to help via phone with “JustAnswers”. He was good but only got back after 2 days and I cancelled my trial which lead to auto payments per month. But, he has access to wiring diagrams and service manual I couldn’t find on internet.

FYI, all auto manufacturers have service manuals available to everyone (it’s required by law). They do, however, charge for access but depending on how much work you do on your own car may be worth it (they also often sell “one-time” access where it lasts for a few days to cover specific repairs).

https://techinfo.toyota.com/techInfoPortal/appmanager/t3/ti?_nfpb=true&_pageLabel=ti_home_page&contextType=external&username=string&challenge_url=https://techinfo.toyota.com/techInfoPortal/login/techinfo&password=secure_string&request_id=8403569659581795437&authn_try_count=0&locale=en_US&resource_url=https%3A%2F%2Ftechinfo.toyota.com%2F

-Jim

On my Jeep Grand Cherokee it happened because a switch broke in the rear window latch mechanism which caused the computer to think it was always open. Since it was the Grand Cherokee it had the display that showed the rear window as always open so it was an easy diagnosis and a $10 fix.

Well, like the saying goes. It’s a present that keeps on giving. I installed the new latch with the locking sensor and actuator. Both OEM and still doesn’t work. I’m going to check to see if connectors are providing voltage. Should be 12 volts

I was able to check the voltage to the latching motor… 9.6 v. I was expecting 12. Could this be the problem. And where are those volts draining to? Any ideas from here ? Thanks