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Scan Tool not connecting...

gn85

Full Member
Joined
Jun 24, 2006
Messages
1,212
Location
Maryland/ Germany
Hey y'all,

I usually don't have many questions because I can just search, read and find the answers to my questions.  But for some reason the SEARCH feature wasn't cooperating with me.

A week or so ago, when it was really cold out, I let the truck warm up for a minute.  When I came out, the CEL was flashing.  When I had first started the truck, it was running a little rough.  However, warmed up it was idling fine.  So I thought it was a misfire.  I drove to work without incident.  Came home from work and no CEL.

I have an OBD2 scan tool.  I plugged it in and was getting a strange message basically saying I wasn't connected.  I put new batteries in the scan tool, still nothing.  I thought my scan tool may have gone bad.

Last night, my wifes car threw a code.  I tried the same scan tool.  Worked!  Code P0442.  WHEW... only the gas cap.

I tried my Avy again... still no connection.  Ruh roh. 

Fortunately, I haven't had any more CELs on the Avy.

**SUMMARY**

-- '03 Avy flashes CEL on cold morning
-- Scan tool fails to connect to Avy
-- Scan tool connects successfully to wife's car.

Thanks for any help or ideas.
 
Does your cigarette lighter work? Same fuse for both the OBD port and the lighter, check for a bad fuse.
 
Z66 BUTCH said:
Does your cigarette lighter work? Same fuse for both the OBD port and the lighter, check for a bad fuse.

Thanks!  That was the problem.  Not sure what blew the fuse, but it was blown. 

There were no codes stored.  Guess I'll have to wait 'til next time to see what the problem was.  But at least, now I can do it.

Thanks again.
 
WTG Z66 Butch.  (y)
 
It happened to me, and SURPRISE!! I remembered.  :eek:

I had a bad phone charger cord that caused mine to blow the fuse.
 
It happen to me also, with my cig lighter is on the bottom a dime dropped into it.
 
What codes did you get?

Mine were p0171 p0131 and p0300 with about the same conditions as yours. My scanner shows live data and I was able to read the Voltage of the O2 sensors and sensor 1 bank 1 was blank, 0.0 V in all conditions even when going really rough. The other sensors are fluctuating in voltage.

Could be a vacuum hose or the intake manifold gaskets as well, at least thats what I was able to figure out by searching  (y)

That day the search-engine worked, but it's darn slow  :beating:



 
Somni said:
What codes did you get?

Mine were p0171 p0131 and p0300 with about the same conditions as yours. My scanner shows live data and I was able to read the Voltage of the O2 sensors and sensor 1 bank 1 was blank, 0.0 V in all conditions even when going really rough. The other sensors are fluctuating in voltage.

Could be a vacuum hose or the intake manifold gaskets as well, at least thats what I was able to figure out by searching  (y)


That day the search-engine worked, but it's darn slow  :beating:



No codes were stored.  It still runs a touch rough when really cold.  When the temps drop back down, I'm sure it'll do it again.

Thanks for all the help.  Like I said, I usually don't ask for help because the info is here already. 
 
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