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Topic: OBD-II scanner won't read on '06 Dmax

Posted By: longrider1100 on 06/08/12 01:10pm

Our check engine light is on steady and the OBD-II scanner won't read, nothing, nada. The dealer wants $90.00 to read the code but before we do that I thought I would see if anyone here has any ideas. We checked the fuel cap, it's OK. The truck runs like it always has. Thanks in advance.


Time to plan to camp.


Posted By: AVid on 06/08/12 01:19pm

If all you need is the code read, take it to you local auto parts store. Around here, Auto Zone will do it for free.


Posted By: ib516 on 06/08/12 01:37pm

It's probably a deeper level of fault code (or a transmission code) than a normal scanner can read. I think the dealer is your only option.


2010 Cougar 322QBS 5er
2001 Dodge 2500 Quad, 4x4, 360 gas, 4.10, auto - SOLD
2002 Dodge 2500 Quad, 4x4, 5.9L CTD, 3.55, auto - SOLD
2007 Dodge 3500 SRW Mega, 4x4, 5.9L CTD, 3.73, auto - SOLD
2014 RAM 2500 Crew Cab, 4x4, 6.4L Hemi, 4.10, 66RFE auto
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Posted By: gmcsmoke on 06/08/12 01:44pm

may need an OBD II/CAN reader


Posted By: longrider1100 on 06/08/12 01:22pm

AVid wrote:

If all you need is the code read, take it to you local auto parts store. Around here, Auto Zone will do it for free.


Did that twice, the scanners won't read anything.


Posted By: hallock5 on 06/08/12 01:25pm

Any chance you just fueled up before it came on? Running an exhaust brake? I have perfectly running Ford 7.3 that activates my CE light when those 2 things happen. If I let it sit overnight, it goes out, never to come back on until I run exhaust brake and refuel.


2008 Jayco Eagle Superlite 28.5RLS
2002 Ford 4x4 SuperCab 7.3 (Jr International) Diesel

Sad to say, time to sell to a good home.



Posted By: RedG on 06/08/12 01:55pm

Check your cigarette lighter fuse. If it's blown, the OBD port is dead.
Fuse labeled LTR in underhood fuse box is for OBD port and one of the aux power ports


2005 Newmar Dutch Star 4024 DP 370 Cummins
Towing my 2012 Malibu w/Blue Ox towbar & Patriot brake system



Posted By: NewsW on 06/08/12 01:56pm

Tell me what make / model of OBD2 code reader you are using, and how old is it (from date of manufacture).

Chances are... it is too old.

Is it syncing to the OBD port --- there should be an indication.

If it bombs there (no sync, no proper communication, then start with an OBD port issue like power suggested above).

Short solution is to hit Autozone etc. and see if theirs will read it. If theirs is not connecting... you have isolated it.

Longer solution is a more up to date reader.

Before you panick -- tell me more about the symptoms that led to the code.

Have you tried to reset the computers?

Even if it has a code --- always erase code, reset computers and see if it comes back before you do diagnostics and repair.

* This post was edited 06/08/12 03:58pm by NewsW *


Posted By: copeland343 on 06/08/12 03:58pm

Diesels do not use OBD2 or CAN you have to use the correct scanner like a Auto Enginuity Scanner.


Posted By: ib516 on 06/08/12 04:41pm

copeland343 wrote:

Diesels do not use OBD2 or CAN you have to use the correct scanner like a Auto Enginuity Scanner.

I don't think this is right. My diesel is OBD2 and has CAN-BUS, and I can scan it's codes with my hypertech tuner or Scangauge2. Both work.

My buddy programmed his Duramax with a Hypertech tuner (OBD2) and he can scan his as well, so the above statement is not entirely true for the Duramax either.

I do however, think there are some codes like transmission and SRS (airbag) related that a generic OBD2 scanner will not read on some vehicles.

I say again, likely a trip to the dealer is in order.


Posted By: ronfisherman on 06/08/12 04:43pm

If a scanner does not display anything. Then as already stated you have a blown fuse. Your Duramax should read with any OBDII reader.


2004 Gulf Stream Endura 6340 D/A
TST tire pressure monitor system
2012 Chevy Captiva Toad
Kodiak Chassis Class C Forum



Posted By: ib516 on 06/08/12 04:43pm

RedG wrote:

Check your cigarette lighter fuse. If it's blown, the OBD port is dead.
Fuse labeled LTR in underhood fuse box is for OBD port and one of the aux power ports

This is true in most vehicles. The #16 pin (lower left) on the OBD2 port is live with 12v as long as the battery has juice.


Posted By: NewsW on 06/08/12 04:55pm

copeland343 wrote:

Diesels do not use OBD2 or CAN you have to use the correct scanner like a Auto Enginuity Scanner.



Unfortunately, Federal Law require all vehicles to be equipped with an identical OBDII plug.

Quote:

1996: The OBD-II specification is made mandatory for all cars sold in the United States.


Quote:

2008: All cars sold in the United States are required to use the ISO 15765-4 signaling standard (a variant of the Controller Area Network (CAN) bus)



http://en.wikipedia.org/wiki/On-board_diagnostics


What you are correct in is that no basic OBD II reader covers the full set of codes.

There are manufacturer specific, and diesel specific codes that are only covered by more sophisticated devices like Autoengeunity.

Then there are special codes for transmissions, ABS, Air bags, etc. that all have and need specialized readers / etc.

The dealer grade tool (e.g. Ford IDS) will do things like allow the user to program certain operations, e.g. move a EGR valve and see if it works, sweep the turbo vanes, deactivate one cylinder at a time, etc. to really help the tech diagnose issues.

The real sophisticated element is its integration into service procedures, diagnostic tests, etc. and being updated to the best data available.


Posted By: Interlude on 06/08/12 05:35pm

I have a 2006 Duramax and my Scanguage II reads it perfectly. Your scanner ot connection must be bad.


Craig and Patricia
2006 Jayco Seneca 34SS .. Double Slide .. Duramax Diesel 6.6lly

Click Here for a Slideshow Tour.
.



Posted By: longrider1100 on 12/29/12 07:15pm

Sorry I forgot to update sooner, but I changed the glow plug and reset the light and that's it. No light and the glow plugs work fine.

After removing the plug I thought maybe it was the connection due to the location behind the wheel so I checked the plug and it was dead. I did clean the connection as best I could given the tight location. Thanks again for all the help.


Posted By: copeland343 on 06/08/12 06:55pm

ib516 you are correct the hypertech tuner will work and read diesel codes. The regular scan tools will not read all of the diesel codes, you have to have a reader that will or go to the dealer. The scanguage 2 will read some of my trucks codes but the hypertech will read most of them. Just saying check before you go buy one.


Posted By: Turbo Diesel Dude on 06/09/12 07:32am

On my 2011 with 44000 miles, Asheville Chevrolet wanted $100 to read and reset my Low Quality Exhaust Fluid lite even tho it was still under the Emissions Warranty. Needless to say I just drove off. It comes and goes along with the SES lite. I think you can unhook the batteries momentarily to reset the computer. JMHO. Had a wrench plug his OBD scanner in to reset the SES lite, but couldn'd read the code, but it eventually went out. The lite that is.


charles weidman


Posted By: longrider1100 on 06/09/12 04:29pm

RedG wrote:

Check your cigarette lighter fuse. If it's blown, the OBD port is dead.
Fuse labeled LTR in underhood fuse box is for OBD port and one of the aux power ports


BINGO! Found the fuse labeled CIG LTR under the hood in the lower right corner. It had a blown 10 amp fuse and called for a 15 amp. We replaced it and checked the DC plug and it was hot.

Next we disconnected both batteries and reconnected, the check engine light was still on. Off to Advance Auto.

Their OBD-II scanner read the code although he said there are dealer codes that it won't read. The code was "PO678 Cylinder 8 glow plug circuit". He said to google it just to make sure. Saved our $90.00 dealer charge for now.

Thanks again for all the help.


Posted By: NewsW on 06/09/12 04:30pm

Good for you.

Sounds like you have a bad glow plug or glow plug wire, and after that, the controller.

Old fashioned sleuthing now.


Posted By: RedG on 06/09/12 06:40pm

The glow plugs going out is fairly common on the LBZ's. They're not that hard to change. Just soak it down good before changing. It's a nightmare if you break it trying to get it out. Haven't heard of many problems with the controller.


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