ToyodaTacoma

Hello everyone! Unfortunately this problem has not resolved, so I decided to update the current condition of the truck with the hope that someone might know exactly what's wrong with it.

Got a 2000 Toyota Tacoma SR5 3.4L 4x4 Manual. I love it. Unfortunately since the day I got it, I have not been able to pass NJ inspection not because of emissions (she passed emissions easily) but because no one could get the vehicle to link up to a OBD2 scanner. At first I did not believe them and figured their scanner was to blame and not the truck. I went out and borrowed an innovo 3130C scanner from autozone and guess what? It worked and I saw all the live data/all monitors were ready/no codes. I even did the alternator test on there just for kicks and again no problems. Took it to the inspection station the next day and failed again due to the same problem. Went home, pulled out the scanner and again it was working HOWEVER after that day I could never get it to connect to any scanner again. I tried the innovo, a harbor freight one, and even a snap-on solus...nothing. Then I tried to find a bad wire and found that all 4 of the wires were good. They all had continuity and I was getting power at pin 16. I noticed it always gets stuck at "detecting CAN" at 96% link progress. It detects various iso9141 stuff. So i figured the ECU/ECM/PCM went bad on it. Just to be sure I took it to a trusted mechanic and he concurred the same and quoted me $1375 including getting the ecu reprogrammed (i guess to match VIN#'s or something). That was way too much money to me so I sent mine out to get rebuilt for $150+ shipping. I ended up getting refunded minus shipping because the guy said he could not fix it or get it to communicate. Then I bought a "new" refurbished unit from autoecmstore.com with matching part numbers and everything for $500. It came in this morning, the truck started right up (although the old ecu started and drove fine as well). I still cannot get the scanner to communicate with the truck. Is this because the battery was disconnected? Do I have to do drive cycles just for the scanner to communicate? I don't think that's the case because even if the emissions systems were not ready, it should be able to connect.Is it possible I got a bad ecu unit? I checked for and cleaned corrosion, made sure the pins at the port were all the way in, checked the two ecu fuses in the cabin drivers side, checked the OBD2 fuse in the engine bay and everything checks out with the multimeter as far as continuity. All the interior lights work, the cigarette lighter port works. What am I missing?? It is driving me crazy having seen with my own two eyes a working scanner for two days and then boom never again. What do you experts think? Perhaps a ground problem? If so can anyone list all the grounds to check that might cause an issue like this? The truck has been off the road for a month now and I miss it.

Thank you

wyoming9

iTrader: (1)

Have you ever cleaned the OBD II plug with electrical cleaner ???

I have had several that would ring out with the Meter but when plugged in will not communicate . Yet look fine to your naked eye

Bent pins

physical damage to wires

All the ECM grounds are tied together when new they are on the left side of the intake manifold. With a bad ECM ground it most likely would not even start

No such think as ECM programing just plug it in.

You have checked you have battery voltage through the Fuses needed for the OBD II system ??

It would not be the first time a fuse was loose in the socket .

Ignition circuit issue that the voltage is not getting where it needs to go poor connection / physical damage .

Just where in New Jersey ?? Your not that faraway if you need some in person help

Good Luck in any case

ToyodaTacoma

Thanks for your response! Yes I have cleaned the connector with CRC electrical cleaner and used a little pick to make sure there was not any corrosion. I am getting 12.35 volts at the obd 2 fuse in the engine bay with the truck off and around 14 with it started. The one under the dash had voltage as well. I did not suspect the grounds next to the intake manifold because as you said it probably would not be running as well as it is if those grounds were compromised. I have not yet checked the ignition circuit though! I'll have to tackle that sometime this week either friday or saturday. I've been working 7 days straight..and I would not mind some help haha. I live in Galloway about 15 mins outside of AC near Stockton University. Thanks again.