Hey guys, anyone have any issues with the ALDL port not communicating? I'm OBD2 and have used lt1edit before to do some programming. I tried to connect last night and it was taking forever to read. so I stopped LT1edit and tried Autotap. The light on the autotap was lit for the vehicle so I'm pretty sure it's getting power. However, Autotap couldn't detect the car. I then tried plugging in a obd2 scanner and nothing. I checked all the fuses on the in the dash fuse panel and they are all good.

One thing that is not happening is when I plug in a cable, I'm not hearing the cooling fans turn on at all. I tried different things too, like car in 1st gear, brake up, door closed, etc...no dice.

Any thoughts on how I can troubleshoot further?

 

talked to the guys at carputing, i think my serial to usb cable is the culprit. apparently, sometimes they work, sometimes not, sometimes takes forever. so i ordered a pcmcia serial card. we'll see what happens

 

How could your USB<-->232 adapter cause your standalone OBD2 reader to fail?

 

i'm using a scan guage which doesn't give me any reading. all i see is connecting. so the usb to serial cable isn't in play.

i did get the new pcmcia card today and no luck still, can't get it to read. The autotap is not reading either. i'm able to read other cars, but cannot get this camaro to read. my last good communication i wrote a new file via lt1edit. car runs fine, just can't do any more programming.

 

I know you checked the fuses, but check the cig lighter fuse again.

 

yup i did that one again. The autotap has a light on it for the vehicle which is a good test for whether the fuse is blown. Also had a phone charger in the cig lighter that has a light on it so i could see that it was lit too. My test was to pull the fuse with the items plugged in and sure enough pulling the fuse kills power to the cig lighter but also the aldl. It's got power and it's steady.

lt1 edit keeps trying to connect but keeps timing out.

autotap - can't detect the car

scan guage - all i see is 'connecting...' as a message

what are you guys using for you com settings? default? any kind of flow control? Xon/Xoff; hardware, etc.?

 

Sorry to hijack and bring up an post that's kinda old, but I'm having the same problem. Mine's a 94/OBDI.

I tried to do some logging/check a SES with Datamaster, and it says "The ALDL is working, but no PCM is detected". I also tried to read the PCM with Tunercat, and it says "cable failure".

Any help would be appreciated.

 

"tried to do some logging/check a SES with Datamaster, and it says "The ALDL is working, but no PCM is detected". I also tried to read the PCM with Tunercat, and it says "cable failure"


Can you start the car since you got that error?
Do your fans run constantly in accessory mode?

 

Yes, I've driven the car a couple times since then. The fans I'm not sure of, but I don't think so. My fans have never come on with key on/engine off, bu I will check tonight when I get home from work just to be sure.

 

By accessory mode, do you mean key on/engine off, or the key turned backward into the actual accessory position? If you mean KOEO, then no, the fans didn't come on tonight when I checked that.

 

I meant KOEO.
I had the same error but my PCM was fried. If you're still driving the car than it can't be that...

Actually I think my fans came on after I pulled all the PCM fuses.

It seems you have a different issue anyways.

 

sorry to bring this back, its old i know. But i just had a question. the ALDL gets its power from the same place the cigarette lighter gets the power from? I tried hooking up a scanner but would not turn on. I have a 94z28 with a 12 pin ALDL

 

'94 z28 does not have +12V at the ALDL connector, if you have a scanner or a cable that requires external voltage vs internal supply to operate it should have a cigarette lighter attachment. Only pins in '94 ALDL are A - ground, B - Diag request to PCM (only used in expensive shop analyzers), G - Keyless entry only, M - Serial data to/from PCM. Pins A and M are used for reading, scanning and programming the PCM. Pin A goes to chassis ground so in effect there is only 1 wire (pin M) that can cause an ALDL connection failure.. Personally I have never seen this wire cause a problem on any forums. Connection failures are always incorrect scanner, or software, or incorrect cables from external equipment.

 

Since this got bumped back up, I figured I would give an update.

I sent my laptop and cable to Andrew at AKM Cables (who I bought the cable from). He checked it all out and found the cable to be the problem. He made me up a brand new cable, and all I had to pay was shipping back & forth. Great guy who stands behind his products.

 

Bob's correct, scanners (like OTC or Snap On) require either an internal battery or a connection to the cig lighter adapter for use on an OBD1 connector. OBDII style connectors *do* have +12V available, but OBD1 connectors do not.

And yep, sometimes cables do break/fail. Very, very rare, but it does happen, and I do try to take care of my customers.