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Discussion Starter · #1 ·
Okay guys, I've done as much research on here as I can and haven't found any cases quite like mine. Here's what I'm up against:

I got the big red X and "Contact Dealer." Of course, it didn't set off a CEL or any trouble codes. It was scanned while active with my OBDII, and with a TechII at the dealer. Found nothing.

The X is still up and has been there for over a week now. The car drives great, and everything functions as intended. However, the odometer is frozen at 63,541. The trip odometer is frozen too. That also means my estimated MPG is now stuck at 0. My fuel range eventually drops to 0, but when I fill up it still shoots up to as high at 100-something.

I've disconnected the battery, checked every single fuse (under the hood, by the battery, and in the driver's footwell). I've double-checked as many grounds and connections as I could visibly/easily locate under the hood.

:dunno: My only idea is either something in the cluster has actually failed, or somehow the battery is effecting it. I do still have the original battery in there.

Anybody have any ideas? Thanks in advance for any/all suggestions!
 

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This does not look good. If the service dept *can't* even figure out what might be wrong (using that do-all/find-all computer), where *can* you go for a solution.
This might be a last ditch possibility>>>> There is a 4 pin connector (as stated in the service manual) that has 3 wires passing thru its disconnect halves. One is 12 vdc, another is a ground, and the 3rd is a low speed data bus communication wire that circulates the I/P health signal. If I read it correctly, if that signal is lost, the module (I think) defaults to something ???
YOU could (if not to painful due to body position required), find, separate, examine, and reconnect that connector (X241 as labeled in the manual). Maybe its experiencing a weak comm or reduced voltage condition at this time.
It says its location is "instrument panel harness to the driver information center harness". It says its to the left of the center stack, behind the I/P area. Possibly a little pain involved trying to verify this, as a possible source of the problem (if you choose).
 

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Discussion Starter · #3 ·
Yeah, it was a pretty awkward moment when I told the dealer service guy that I wasn't going to pay for their TechII scan if it found nothing, but I'm glad I said it. ...I knew from my research on here that even their tool wasn't going to find anything.

Their only response anyway from the start was that if there was no CEL or something obvious, that it was either going to cost me an arm and a leg for them to have the car for an unknown amount of time to troubleshoot, or that I should drive it until it falls apart and then bring it in.

I really appreciate your advice GOPHERIT and that's something I'm definitely going to try (if my last ditch approach to change the battery doesn't do anything - which I'm doubting it will). Maybe after I try to find a super cheap cluster to swap in and try for a mile or 2 as well.... but that's all I had in mind anyway.

Thanks again, GOPHERIT

...anybody else have any ideas?
 

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Yeah, it was a pretty awkward moment when I told the dealer service guy that I wasn't going to pay for their TechII scan if it found nothing, but I'm glad I said it. ...I knew from my research on here that even their tool wasn't going to find anything.

Their only response anyway from the start was that if there was no CEL or something obvious, that it was either going to cost me an arm and a leg for them to have the car for an unknown amount of time to troubleshoot, or that I should drive it until it falls apart and then bring it in.

I really appreciate your advice GOPHERIT and that's something I'm definitely going to try (if my last ditch approach to change the battery doesn't do anything - which I'm doubting it will). Maybe after I try to find a super cheap cluster to swap in and try for a mile or 2 as well.... but that's all I had in mind anyway.

Thanks again, GOPHERIT

...anybody else have any ideas?
Does the speedometer work?

If so, the vehicle speed sensor is working. Odometer and Speedometer both start with the VSS. If the speedometer is working, you know that the TCM is receiving the VSS signal and it is passing through the high speed LAN to the BCM and from there to the cluster via low speed LAN. It looks like the cluster receives both the speedometer data and odometer data via the low speed LAN so if the speedometer works you know that the communication is there.

You have three possibilities as I see it:

1. Check the fuses
2. You have a bad cluster
3. You have a bad Body Control Module


Also, did they scan the BCM for codes?
 

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Funny how the car says contact dealer. You contact the dealer. Take it into the dealer Wait for them to troubleshoot the problem here is there response...:dunno:. Leave the dealer and start the song and dance all over again. I would like to assume they scanned everything they possibly could with the Tech II, but I have learned to not assume anything nowadays. Subscribed for updates.
 
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Discussion Starter · #6 ·
PONY MAN, I got to sit with the service tech and watch the scan. It was my first time actually seeing one of those TechII things in action, and it appeared as if he was going thru every option he could, but I can't be sure.

kgenesse that's all really great! I reeaallly appreciate that information! Helps me narrow it down a little more. Everything works perfect EXCEPT the odometer/trip odo. Both the digital and analog (needle) speedometers are functioning and accurate. Even if I enter into Engineering Mode, everything there is working and accurate too.

Do you have any ideas on how to further test the cluster? That's really starting to make more and more sense. Sucks since I doubt there's any chance the cluster will be covered by powertrain warranty...

I hate the idea that my only option seems to be to hit ebay and buy a crap cluster that I'll literally put in for 1 or 2 miles just to see if everything's functional.
 

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Discussion Starter · #7 ·
... sorry kgenesse I didn't see that you asked if they scanned the BCM for codes. I'm really not sure, and I didn't think about the BCM at all while I was there.

Working for an automotive supplier, I've definitely seen a lot of strange BCM failures, but in our experience we always have to go to the BCM supplier directly (Conti in our case since I specifically work on Ford stuff). That and it's usually easy for us to diagnose since the BCM tends to turn the car into a brick.

I will definitely have to look into the BCM too. Do you know if the TechII can scan the BCM? Or any idea who is the supplier of our BCM? Maybe it'll happen to be a supplier I can find help for thru my work.

Thanks again!
 

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I don't know who supplies the bcm, and the only way to test the cluster is to find someone with a G8 and switch clusters or buy one. If you have no blown fuses and the cluster is good, you need to replace the BCM which requires reprogramming.

And yes a tech II can scan the BCM. Most good quality (snap-on, genisys, etc.) can.
 

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The WD is very basic on the I/P display functions. But it might be that there is a device mounted on the massive circuit board, that interprets and converts the analog MPH and maybe the RPM it see's, into the odometer/trip/fuel average, display as seen in the DIC. If so, maybe it crapped out. That probably means the only fix for it, would be an entire (new or re-configured used one for your VIN) I/P panel.
I've only seen one big X display show up on another members car, and it was due to one of the fuel tank quantity sensors failing. But he was also getting a bad fuel remaining display in his gauge to go along with it. Since yours works good (the way your posts are written), that does not seem to be the case here.
 

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Discussion Starter · #10 ·
The WD is very basic on the I/P display functions. But it might be that there is a device mounted on the massive circuit board, that interprets and converts the analog MPH and maybe the RPM it see's, into the odometer/trip/fuel average, display as seen in the DIC. If so, maybe it crapped out. That probably means the only fix for it, would be an entire (new or re-configured used one for your VIN) I/P panel.
I've only seen one big X display show up on another members car, and it was due to one of the fuel tank quantity sensors failing. But he was also getting a bad fuel remaining display in his gauge to go along with it. Since yours works good (the way your posts are written), that does not seem to be the case here.
Yeah, I had read about a few cases of the big red X and what it ended up being for others on the board, but I don't have any of their symptoms. I was reeaallly hoping I was going to experience the fuel gauge issues and have the same problems others have --- plus that's covered under powertrain warranty from what I understand.

I've already gone thru 1 full tank, and I'm almost thru my 2nd full tank. Everything involving the fuel gauge and even the total gallons left screen in Engineering Mode appears to be spot on as well.

Well, I'm on the hunt for the cheapest cluster I can find for now. I guess that'll be my first step from this point.
 

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However, the odometer is frozen at 63,541. The trip odometer is frozen too
Perfect , I don't see a problem if this is happening. To bad it didn't freeze at 500 miles . Any way. Good luck gettin her fixed.
 

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Okay guys, I've done as much research on here as I can and haven't found any cases quite like mine. Here's what I'm up against:

I got the big red X and "Contact Dealer." Of course, it didn't set off a CEL or any trouble codes. It was scanned while active with my OBDII, and with a TechII at the dealer. Found nothing.

The X is still up and has been there for over a week now. The car drives great, and everything functions as intended. However, the odometer is frozen at 63,541. The trip odometer is frozen too. That also means my estimated MPG is now stuck at 0. My fuel range eventually drops to 0, but when I fill up it still shoots up to as high at 100-something.

I've disconnected the battery, checked every single fuse (under the hood, by the battery, and in the driver's footwell). I've double-checked as many grounds and connections as I could visibly/easily locate under the hood.

:dunno: My only idea is either something in the cluster has actually failed, or somehow the battery is effecting it. I do still have the original battery in there.

Anybody have any ideas? Thanks in advance for any/all suggestions!
Hello.

I am sorry to hear that you are experiencing an issue and cannot pinpoint the problem. Can I be of Assistance?

Jennifer T,
GM Customer Care Service
 

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As a possible last ditch try, before maybe having to go the I/P R&R route, they do show that there is a dedicated "Instrument Cluster Programming and Setup" procedure that can be performed with that big time GM computer they have/use.
Maybe you can visit *that same* nice tech you talked about (that let you watch that previous scan tool checkout), to see *if* and *how much* it might be to run a delete and re-program/setup on your current I/P. If there's a current glitch in the existing I/P program, maybe it can be corrected for a nominal fee. All thou *not accumulating miles* logged in, is kinda nice also.
 

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Discussion Starter · #14 ·
As a possible last ditch try, before maybe having to go the I/P R&R route, they do show that there is a dedicated "Instrument Cluster Programming and Setup" procedure that can be performed with that big time GM computer they have/use.
Maybe you can visit *that same* nice tech you talked about (that let you watch that previous scan tool checkout), to see *if* and *how much* it might be to run a delete and re-program/setup on your current I/P. If there's a current glitch in the existing I/P program, maybe it can be corrected for a nominal fee. All thou *not accumulating miles* logged in, is kinda nice also.
hahaha oh man, trying to work with a dealer on that kind of level! This already sounds like a PITA! :banghead:

GOPHERIT can I ask, how/where did you find out that they have the ability to do "Instrument Cluster Programming and Setup?" Was this something you found or know that they can do in house at the dealer, or do they in reality take their time and send out the cluster for programming? Just curious what I'm up against. I feel like I have to be prepared for battle every single time it comes to going to a dealer for help!

Also, I thought I read on here on before that dealers have always refused to work on clusters like that, or reprogram clusters that people bring in, say, from ebay (ie: when someone finds the red/black cluster and wants to replace their plain black one). Seems like they're always quick to just say "no, we can't" without any hesitation.

I'm going to talk to my dealer service guy about this tomorrow morning though, and who knows ---maybe that'll be the magic bullet! Thanks so much for offering this information as a possible solution before I drop ~$100 on an ebay cluster JUST for troubleshooting!
 

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Discussion Starter · #15 ·
Hello.

I am sorry to hear that you are experiencing an issue and cannot pinpoint the problem. Can I be of Assistance?

Jennifer T,
GM Customer Care Service
Thanks for the offer Jennifer

I appreciate that you guys are on here and always offer to help with research or whatever you can. I'm just not sure yet what I need. It looks like some of the other members here have given me a solid direction I need to pursue first, but I certainly appreciate the offer and I may ask you soon for some assistance too in the near future. Thank you!
 

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^^^ It talks about it in the service manual on pages 6-8 and 6-9 (Programming and Setup) section. In effect it tells the tech that *he must* have all the latest TIS information, as well as a little of this and some of that etc. etc.
It sure sounds like its do-able. But will a tech agree to look up the info and possible support things, that may be required *to* due it.
 

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Discussion Starter · #17 ·
And the problems keep coming!

Today now, out of nowhere, the ABS light comes on and also shuts off trac control.

Codes I pulled using a scanner from OReilly's:
1: C0045 rear left wheel speed sensor
2: C0050 rear right wheel speed sensor
3: C0245 ? Can't find anything about this on our board, but google searches seem to only bring up this code for guys with GM trucks (and GTOs) where the owner changed tire sizes from stock. I have NOT done this. I have always been running on the normal V6 stock 18s with 245/45's. I did get new tires, but that was 6+ months ago and I only got the code today for the 1st time.
4: U0073 CAN Communication Error (not sure on this one, but others on the board seem to have discovered that the scangauge itself can set this when plugged in)
 

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^^^^^ Those all all good fault #s for are cars. Another member had an ongoing problem a lot like this. It turned out to be a failed F1---- COMM ENABLE fuse in the underhood fuse box. It powers a circuit that *wakes up 2 important modules* so they will start communicating on the data bus. When failed, it would turn off the TC and I think will also fault the ABS system along with it. You could take a peek at that fuse and its control relay R2--- COMM ENABLE, to verify that it operates at key turn on.
 

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Discussion Starter · #19 ·
^^^^^ Those all all good fault #s for are cars. Another member had an ongoing problem a lot like this. It turned out to be a failed F1---- COMM ENABLE fuse in the underhood fuse box. It powers a circuit that *wakes up 2 important modules* so they will start communicating on the data bus. When failed, it would turn off the TC and I think will also fault the ABS system along with it. You could take a peek at that fuse and its control relay R2--- COMM ENABLE, to verify that it operates at key turn on.
GOPHERIT --> I feel as tho I should be paying you for your service!

Okay, so here's what I did tonight:

1: Removed original battery
2: Swapped F1 & R2 with known working/good fuse/relay
3: Installed new battery (which has been fully charged)

...it's already 1AM tho and been a long night. I haven't actually connected the negative battery terminal yet, but will in the morning and see what happens.

Is there an easy way to confirm that F1 & R2 are active/working inside the fuse box? I at least know for sure that I have a good fuse and relay in those spots, but not sure if that's going far enough. I'll update in the morning when I reconnect the battery and start her up.
 

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If by chance you have no success, read this:

Action Taken When the DTCs Sets

The module suspends all message transmission.
The module uses default values for all parameters received on the serial data circuits.
In the TCM, DTC U0073 will cause the transmission to go into default gears.
In the ECM and TCM, DTC U0073 will cause the malfunction indicator lamp (MIL) to illuminate.
The module inhibits the setting of all other communication DTCs.

It sounds like if you engine and transmission are running/shifting okay, it has to be another module. BCM, ABS, Airbag, etc. Since you have wheel sensor codes, it is more likely the ABS module as GOPHERIT stated as a possibility. You need to verify that the ABS module has good power and grounds with the key on using a test light.



Electronic Brake Control Module (EBCM)
Pin Wire Color Circuit No. Function
1 3 BK 350 Ground
2 3 RD/BK 142 Battery Positive Voltage
3 2 OG 3540 Battery Positive Voltage
4 2 BK 350 Ground
5 0.5 L-BU 830 Left Front Wheel Speed Sensor Signal
6 0.5 GY 7127 Wheel Speed Sensor Supply Voltage Left Rear
7 0.5 GY 7128 Wheel Speed Sensor Supply Voltage Right Rear
8 0.5 BN 882 Right Rear Wheel Speed Sensor Signal
9 0.5 GY 7065 Wheel Speed Sensor Supply Voltage Right Front
10 0.5 D-GN 872 Wheel Speed Sensor Signal Right Front
11–13 — — Not Used
14 0.5 BN 2501 High Speed GMLAN Serial Data Bus-
15 0.5 BK/D-BU 2088 Steering Wheel Position Sensor Low Reference
16 0.5 BN/WH 2086 Yaw Rate Sensor Test Control
17 — — Not Used
18 0.5 D-GN 2087 Steering Wheel Position Sensor 5-V Reference
19 — — Not Used
20 0.5 PU/WH 1699 Combined Vehicle Inertial Sensor Signal
21–24 — — Not Used
25 0.5 BN 2501 High Speed GMLAN Serial Data Bus-
26 0.5 GY 7064 Wheel Speed Sensor Supply Voltage Left Front
27 0.5 BN/BK 884 Left Rear Wheel Speed Sensor Signal
28 0.75 L-BU 5986 Communication Enable Relay Supply Voltage
29–34 — — Not Used
35 0.5 BN/BK 2500 High Speed GMLAN Serial Data Bus+
36 — — Not Used
37 0.5 L-GN/BK 5352 Yaw Rate Sensor Test Control
38–44 — — Not Used
45 0.5 BN/BK 2500 High Speed GMLAN Serial Data Bus+
46 — — Not Used

With the key in the on position, unplug the connector and you should have power on pins 2, 3, and 28. You should have ground on pins 1 and 4.

If the ABS module is getting power and has good grounds, you need to try to scan the ABS module and see if it will communicate. If not, the chase begins. But I think you will find it to be a power/ground issue more than anything. If you find that you have no power, then you need to check every fuse with a test light.

Also, the way I read the GMLAN schematic, if the ABS module lost upstream communication (as in broken GMLAN + or - wire), the ECM and TCM would also lose connection as well. So there definitely isn't a problem there.
 
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