OBDii non communication

RLBRUBAK

MEMBER
2002 SUBARU OUTBACK
2.5L
4 CYL
2WD
AUTOMATIC
150,000 MILES

I have done a number of repairs on my vehicle, including replacing the Catalytic Converter and both my O2 sensors. However, I cannot pass the emissions testing because their readers cannot communicate with my computer. All other readers have no issues connecting to my computer, only the ones from the emissions testing facility. It has been explained that the emissions facility relies on the cars' power to run their machinery, but that doesn't explain why every mechanic can communicate but their machines cannot. All my fuses look good, and I have been tested at multiple facilities and multiple machines within the same facilities. I am at a loss. Car is mechanically sound. I have not tested pin 16 on the plug, but that shouldn't be the issue if other readers can connect, right?

1 Reply

STEVE W.

MECHANIC
13,452 POSTS

It depends a lot on what tools the other shops were using, most of the higher end tools use an internal battery for power and don't need power from the ALDL. That said Subaru is one Japanese maker that has a few loose standards on their test connections, one being that many do not have power on pin 16 but instead have it on pin 1. So, the first step will be to use a test light and see if you have a pin 16 and if it has battery power on it. I suspect you will find it has battery power on pin 1 but not on 16. Probably the easiest solution if that is the case would be to simply run a jumper wire on the harness behind the ALDL so that the power connects to both. The reason why many tools will still work is that if the tool says it will work on Subaru and Toyota it likely can draw power from pin 1 or pin 9 as well as pin 16. If you are missing pin 16, the easier thing would be to visit a salvage yard and get another connector from a Subaru with at least 6 inches of wire, then use a pick to release the pin from port 1 on that connector. Then install it into your vehicles connector and connect it to pin ones wire which should be the same color.

Images (Click to make bigger)