Jolls VY SS Ute Project (Jimi Hendrix)

[Fu Manchu]

This is also worth a look.

 

[Jolls]

Thanks Fu, handy piece of information.

I have just spent a couple of hours trying to isolate the issue. I have made a few steps forward and then took a couple back.

So I had a couple of unrelated DTCs (seat belt pretensioner issues) that I did not expect were relevant but I wanted to clear them just in case. I didn't want to fart around with the seats any further so I tidied up the amp wiring so it was hidden, then put the seats back in and connected them up. I also took a bit of fine paper to the key blade and the slip ring contact to ensure I had a good contact for the chip reader.

Hooked up the Tech 2 and cleared all of the DTCs for a fresh start.

Took a deep breath and turned the key

Crank, Crank, Crank

Checked the DTCs - slip ring issue resolved, seat belt pre-tensioners sorted.
New DTCs from the BCM:

• 7 - No Serial Data from PCM - the DTC sets if PCM data is lost for 10 seconds
• 26 - No Serial Data from ABS/ETC - the DTC sets if ABS data is lost for 10 seconds
• 27 - No Serial Data from Instruments - the DTC sets if Instrument data is lost for 10 seconds

New DTCs from Instrument Cluster

• 9 - No Serial Data from BCM
• 10 -No Serial Data from OCC
• 11 - No Serial Data from PCM
• 15 - No Serial Data from Radio (Not connected so expected)

New (Same) DTC from PCM

• P1626 Theft Deterrent System, Fuel System Enable Circuit. The system has reached fuel enable decision point.• The PCM is in Fail Enable Mode due to loss of communication with the PIM after the system received the correct password earlier in the ignition cycle or • The PCM does not receive the password message from the PIM prior to the theft deterrent Fuel Decision Point.

PIM - no DTC

This all now points to a failure in the serial data circuit, That's what I thought anyway so I ran the diagnostic checks and it passed all the checks. I can communicate with each component individually, clear the DTCs as a group and I can individually check all of the internal functions of the components.

It appears that the modules are not communicating with each other. I'm not sure how this occurs given the DLC connection uses the same communications pathway to all of the components.

Does that mean they have lost their linkages and I need to relink the BCM, PIM and PCM? It doesn't explain the Instrument Cluster not receiving data from the BCM though. Scratching my head at the moment.

Any recommendations would be greatfully accepted!

Cheers n Beers
Jolls

 

[Fu Manchu]

I would suggest something else.

Let’s first try a full cap discharge of everything.

Negative terminal disconnect.
Then turn to start
Lights on. High beam on.
Interior lights on
Fan on hi
Put into reverse and then neutral
Toot the horn
Windows up and down

Essentially get everything on to discharge any capacitors in the circuits.
Leave for 30mins.

Then switch off everything.
Double check everything is switched off.
Double check hand brake on and in neutral (or park for auto)

Reconnect negative terminal.

Try to start the car again.

 

[Jolls]

Thanks Fu
I'll give it a crack in the morning. I'll let you know how it goes.
Cheers n Beers
Jolls

 

[Fu Manchu]

It may very well make no difference but it is a basic step to do to eliminate any glitches. It costs nothing but a cup of tea and 35mins of your time.

If it works, it’s a win.

 

[Jolls]

Good to start from a known baseline. I am currently downloading the TIS2000 and a dongle emulator that I will upload onto an old laptop tomorrow as well. That way I can get into the programming/linking side of things if I have to.

I have found that the cluster comes up as a HSV cluster from a WM - I wonder if this is the problem. Although the pervious owner guarantees it was all set up and working together when it was set up as an auto. The PCM was adjusted to manual by a reputable mob but perhaps in doing so has dropped the link. I assume they are simply linked by VIN (would make sense) once the authorisation is provided through the "dongle".

This is something I should have done ages ago because it would eventually be needed. I'm not on the computer side of the house but I am starting to look through the PCM Hacking site looking for a place to start to learn the how to.

Cheers n Beers
Jolls

 

[Fu Manchu]

You can swap clusters with no issue. I used my Calais cluster in my crewman before I had it set up for the Crewman. The car started fine and just had gauges a bit arse about.

 

[Fu Manchu]

But hang on. A WH? A WK maybe?
Try removing the cluster and see if it starts.

 

[Jolls]

But hang on. A WH? A WK maybe?
Try removing the cluster and see if it starts.

The Cluster info came up when I first tried to connect the car - HSV symbol build 3 by someone (didn't take a note as I expected it would remain there on start up) and build level WM I may have misread a H for an M - just seemed odd to me at the time.

This info is gone since I programmed it to Manual - it doesn't show on the Tech 2 at all it was an initial screen on the MFD.

When polled by the Tech 2 it comes back with VY SS Level 1 and all functions are correct. I have checked it thoroughly with the Tech 2 and everything functions in accordance with the levels indicated.

I do have a spare cluster in the VZ that I can use if need be.

It may very well make no difference but it is a basic step to do to eliminate any glitches. It costs nothing but a cup of tea and 35mins of your time.

If it works, it’s a win.

So I went through the full cap discharge this morning. Then turned the key to on, went through its sequence and MFD read systems OK. Confirmed with the Tech 2 that the communications errors were historic and the no start anti theft was also an historic DTC. A glimmer of hope.

Checked communications with all of the modules - 100% (less radio)

Followed the serial data diagnostic steps and came up with System OK.

Turned the key

Crank, crank, crank

Repolled the BCM - three lost serial data messages are now current - PCM, ABS and Instruments
Repolled PCM - P1626 Theft Deterrent System, Fuel System Enable Circuit is now current

So brains trust - I have detailed my diagnostic process so far below. Have I missed something obvious and am I heading in the right direction?

When the key is inserted into the ignition switch cylinder the BCM polls the key through the slip ring and contact pin to check the remote code on the key using the remote code reader. If the code is correct the BCM deactivates the theft deterrent system. Well the security light on the instrument cluster is off as per the circuit description. (BCM is able to communicate with the instrument cluster)

The system completes it self check. The Instrument Panel Cluster provides visual information to the driver via the MFD. This means that the instrument cluster is sending and receiving serial data.

From the Manual (with my problem solving thoughts)

On vehicles with a GEN III V8 engine, the BCM polls the PIM and sends an encrypted BCM / key security code when the ignition is turned on.

When the ignition is in the on position I can only see historic DTC. So at this point everything is good!​

The security code is received via the BCM slip ring, or via the remote receiver in the event of no slip ring communication. The PIM compares the received security code with its stored security code and if the codes match, enables continued engine cranking

The engine cranks so the PIM receives the code. Correct? Otherwise engine cranking would cease (I expect)​

and sends a separate encrypted security code to the PCM. The PCM compares this code with its stored security code and if the codes match, enables injector fueling to continue. The PIM returns an OK TO START message to the BCM, which tells the BCM to jump from SHORT
LOOP mode to LONG LOOP mode.

I expect this is the failure point and there is a mismatch between the code in the BCM and the PCM. The PIM is not involved other than to transfer the data between the BCM (UART - fixed pulse 5V to ground @ 8.3kbits/s) and the PCM (Class 2 Comms - long/short pulse 0-7V @ 10.4kbits/s) ​

So during the start up sequence the PCM shuts down the fuel and ignition circuits as part of the theft deterrent system. It does so because either there is a mismatch in the code or it loses communication with the BCM.

So now to determine if comms fails or the PCM isn't linked. TIS2000 required I think!

 

[Jolls]

I have downloaded the software and son 1 is going to drop over a laptop with a USB to RS232 adaptor so I guess I will have to wait until I can try to link it all up.

In the meantime I will try to repair the centre dash storage pocket using some plastex.

​