No Power Ay Ecm Test Port

[Nail-er]

I have a 2000 GMC Sierra with a 5.3 engine. 71XXX miles

I live in an area which requires emission testing. This is accomplished by pluging into the reader port under the dash (drivers side)

My port is showing no power. They cannot get a reading . No reading, no test. No test ... no license plates.

Where do I start looking? Which pin is the power pin?

I have no check engine light on and the truck runs great.

First time they tried the test, as I was leaving I noticed the gas guage go to empty and the low fuel light came on. Then it would go back to normal. Happened a few times then stopped doing it.

Second time the test was tried, the security message came up. It would not go off till I turned off the truck and restarted it.

Where do I begin? I tried to give all the info hoping it will help.

 

Thanks for any input.

[dlstewart01]

I have a 2000 GMC Sierra with a 5.3 engine. 71XXX miles

I live in an area which requires emission testing. This is accomplished by pluging into the reader port under the dash (drivers side)

My port is showing no power. They cannot get a reading . No reading, no test. No test ... no license plates.

Where do I start looking? Which pin is the power pin?

I have no check engine light on and the truck runs great.

First time they tried the test, as I was leaving I noticed the gas guage go to empty and the low fuel light came on. Then it would go back to normal. Happened a few times then stopped doing it.

Second time the test was tried, the security message came up. It would not go off till I turned off the truck and restarted it.

Where do I begin? I tried to give all the info hoping it will help.

 

Thanks for any input.

 

The test port uses the cigarette lighter fuse. Check that fuse first. Its been so long since I changed one I can't remember if its in the fuse block on the drivers end of the dash or under the hood. I think it may be under the hood.

 

Don

[gmtech4]

you have 2 issues ,not related ,get your fuse under hood to read data and your security issue is intermittant and there is a code in history ,but it cannot be diag'd till its a hard code .you can throw parts at it but at the cost....

[Nail-er]

I have a 2000 GMC Sierra with a 5.3 engine. 71XXX miles

I live in an area which requires emission testing. This is accomplished by pluging into the reader port under the dash (drivers side)

My port is showing no power. They cannot get a reading . No reading, no test. No test ... no license plates.

Where do I start looking? Which pin is the power pin?

I have no check engine light on and the truck runs great.

First time they tried the test, as I was leaving I noticed the gas guage go to empty and the low fuel light came on. Then it would go back to normal. Happened a few times then stopped doing it.

Second time the test was tried, the security message came up. It would not go off till I turned off the truck and restarted it.

Where do I begin? I tried to give all the info hoping it will help.

 

Thanks for any input.

 

The test port uses the cigarette lighter fuse. Check that fuse first. Its been so long since I changed one I can't remember if its in the fuse block on the drivers end of the dash or under the hood. I think it may be under the hood.

 

Don

 

 

 

 

 

Thanks for the tip. The cigarette lighter hasn't worked for a while. I never would have put the two together. Thanks a HEAP.

As far as the security light, it only happened once right after trying to read codes. Not sure if the reader reverse powered something since the port was dead.

I'll find and replace the fuse and try it again,

 

Thanks again ,

Don

[gmtech4]

no ,the code reader didn't do anything,don't worry about it ,all good now,change the fuse,it is a rather dumb idea for GM to power up the DLC with the cig fuse,kids put pennies in there etc ,I change a fuse every couple of days to scan a truck /car,later

[Nail-er]

Yep, all good now.

The mechanic doing the emission test told me for $80 he would hook it up to the " big computer" then just go thru things till he found the problem. I told him no thanks.

I'm a back yard mechanic myself. I miss the days of BC (before computers) Adjust your points, set your timing and go. You could sit under the hood with your engine. Now you can't see the engine.

Thanks again for the help. Glad you guys are here.

[Nail-er]

Replaced the fuse today and tested. Pass.... no codes found.

Thanks all !!

[uniteam]

What other thing could I check too ? because the cigarette fuse was OK .. and I can't programmed my 2002 GMC Sierra 1500 HD 6.0L with Hypertech.. No power on DLC connector...

[uniteam]

What other thing could I check too ? because the cigarette fuse was OK .. and I can't programmed my 2002 GMC Sierra 1500 HD 6.0L with Hypertech.. No power on DLC connector...