e9stibi

I was out on a drive today and the check engine light came on. Car was and is driving fine but the CEL remains on. I have am OBD2 reader in the car that I connected to get to the code. After connecting the generic OBD2 reader to the plug and turning the ignition on, the reader started as usual but when I wanted to read the code, it gave me a connection error.

After I came home, I tried my other reader and basically got the same result. I have used the OBD2 readers in the past without any issue. There must be something on in the car.

I did not work on the plug but it was kind of loose because the bolt that holds the plug to the tunnel rattled off a little bit.

Any thoughts what this could be and how to rectify?

Thanks in advance.

MielsOnWheels

Had the same issue with mine. After you start the car, press the button on the key fob again and it should allow the connection. The immobilizer is not allowing the connection to be made.

Steve Weiner-Rennsport Systems

Disable the Immobilizer before using any scan tool.

e9stibi

Thanks for the responses on the immobilizer. I am not 100% clear what I need to do to disable the immobilizer. I connected the scan tool to the car 20+ times and never had this issue:

Here is the procedure I use. Please let me know what I have to adjust:

1. Open locked car with key fob
2. Immediately turn on ignition
3. Connect OBD2 scanner to plug (reader starts up via power from plug)
4. Connect to read codes

When I do step 4, I get the error message of connection error.

Thanks!

nine9six

I would suggest swapping operation 2 and 3.

Also check your OBD II plug for bent pin(s).

Once you unlock the car with the fob, the immobilizer has been deactivated. It will automatically reactivate/arm, in approx 3 mins.

dave97

Does your car have a altered/upgraded ecu, "chipped"?

Steve Weiner-Rennsport Systems

What year is your car?

MielsOnWheels

I do this same procedure, but I insert a step between your #3 and #4..."press the button on the key fob again"...this allows the connection to be made between the reader and ECU.

I have to do this even though I've got Steve's ECU reflash and he defeated my immobilizer as part of the reflash.

Drisump

I actually start the car and my Autel works fine. The reader instructions says you can simply turn on the ignition but I have had no success with that. Cheers

pp000830

If your immobilizer is inactive and you still have an issue it may be power to your reader or a handshake issue. I have the older Durametric cable and found that it regularly has connection issues. Putting my laptop on cord power seems to help. Also trying to read modules other than the Engine first seems to help with engine module access. At time I have to completely disconnect the cable at both end and start over. I also at time press control-Alt-Delete and kill off any Durametric processes I see as running before making a second or third attempt at a connection. If you are using a hand held reader try it with the engine running as this will make at least 13.5+ volts available to the reader to power it and it also is proof positive that the Immobalzer is inactive.

e9stibi

Steve - it is a 97 with GIAC chip.

Never had connectivity issues with different OBD2 reading devices. Kind of strange that I experience issues at the same time the CEL came on for the first time since I own the car.

The pins in the plug look ok but I might take the plug out to have a better view.

Thanks

e9stibi

I will make this test later this morning and will let you know how it went.

e9stibi

I just successfully connected the reader while I had the engine running. Interestingly enough, when I shut down the engine and tried connecting the reader again, it worked.

I would still do not rule out a connector issue but the next time, I will follow the excellent and simple advice to start the engine. Thanks again.

RL is a great place ...