View Full Version : OBD 1?

07-20-2010, 03:56 AM
I've got an 87 GT-S celica with about 205,000 miles. I was wondering
if the "data port" on the wiring harness under the hood is OBD 1?
When was OBD 1 implemented at Toyota? Thanks for any help!


07-20-2010, 04:01 AM
Yes it should be OBD-1

Depending on what your wanting with the system, the car has a built in Diagnosis system.

07-20-2010, 02:02 PM
Good question on when introduced. The CARB (California Air Resources Board) in April 1985 approved OBD-I for all California vehicles sold there. By 1988, almost all cars sold in the US had OBD-I. I remember my dad's 1982 Olds 88 had OBD-I as some US makers were already working with the technology to get ahead of the game. I'm pretty sure Toyota started selling US cars with OBD-I in 1988.

Toyota supposedly introduced serial data access also in 1988 Cressida, which provided sensor values, switch status, actuator status, and other engine operating data. Over the next couple of years, this serial data was universal across all Toyotas sold in the US.

Hope this helps.

07-22-2010, 02:08 AM
Oh sweet I didn't know there was serial data access now I can pull all the values without having to make my own adapter.

07-22-2010, 03:21 AM
I think so. One wire should be carrying the 20 words or so of data for serial information (live data streaming) on post 1988 Toyota vehicles.

Regarding adapters though, you will have to have something that fits over the data link connector (DLC) of OBD-I Toyotas, because the DLC on Toyotas are Toyota specific. Innova makes such an adapter.

07-22-2010, 02:49 PM
My 87 Supra was OBD1 so your Celica should be the same. Quick question if i can hijack this thread for a quick answer .... a 90 GT-Four JDM OBD1 or OBD2? I'm thinking OBD1 but hoping OBD2 (I haven't bothered checking as nothing is wrong with it yet)

07-22-2010, 04:22 PM
If you have the "standard" scanner connector somewhere under the steering wheel on your 90 GT-4 that only OBD-II scanners can plug into, then you have OBD-II.

However, OBD-II systems did not come out yet in 1990. So I'm thinking you only have the Toyota specific data link connector (DLC) under the hood of your car - which would make it OBD-I.

07-22-2010, 04:43 PM
OBD-II wasn't around till around 96ish

07-22-2010, 05:15 PM
Yeah, thats what I figured. Oh well :(

08-02-2010, 05:09 PM
sorry i'm new but why would you want OBDII? i remember on my civic OBDII was a pain to work with and most owners converted to obdI. is there something different on celicas?