Vx commodore warning lights regularly coming on but scan shows no faults logged

[muzza73]

So my 2000 vx V6 has airbag warning light flashing fairly regularly on and off ( mainly off), also for the last few weeks my check engine ,abs, oil, traction lights come on now and then ,when this happens the aircon display has a tiny cross in the right hand corner of display and aircon doesn't blow cold , I went and got Supercheap auto to scan the car and no faults came up at all, even tho the airbag warning light was chiming as he scanned the car, does anyone have a similar experience or advice ? Cheers muz

 

[accentstencil]

Could be one of two things, ABS Module or alternator regulator (probably over charging).
Test the alternator voltage.
If that's fine, unplug the electrical connector at the ABS module, if most of the warning lights go out then that's your problem.

 

[muzza73]

Cheers m8 ,yeah the alternators a new quality unit and I've had the abs issue before, I've replaced the abs module years ago ,so looks like I'll b doing that again, it's strange no faults came up but with the scan ,I thought the computers in these cars logged faults

 

[lout]

when the abs module shorts internally it upsets the aldl network
which means each computer cannot talk to the other
dash shows all warning lights because it does not no what to do
the cross in aircon is because computers cannot talk to climate module
there is no fault recorded because nobody could talk to each other to log one
if you go into dash engineering mode you will find no serial data history codes
Trip computer diagnostic codes
Hold mode and up arrow then turn key to on or start
Release buttons
then
Press Mode = Dash Part Number - e.g. 1731
Press Mode = Mode Switch Voltage - e.g. BV - - - 5.0
Press Mode = Battery Voltage - e.g. V 11.8
Press Mode = Petrol Sender Voltage - e.g. FUEL 02.6
Press Mode = LPG Sender Voltage - e.g. VL 5.0
Press Mode = Remaining Fuel - e.g. 38L
Press Mode = Instantaneous Fuel (Liters per Hour) - e.g. 12.8 L/H
Press Mode = Engine Coolant Temp - e.g. 63 C
Press Mode = Vehicle Speed - e.g. 45 KM/H
Press Mode = Tachometer - e.g. 2380
Press Mode = Park Lamps Switch - e.g. P OFF
Press Mode = Dash Trouble Codes - e.g. t 00 (Press up/down to scroll through any codes, these are not PCM, ABS, etc codes)
Press Mode = Dash Test - All gauges will move, lights will come on and buzzer will sound.
Turn key off will revert to normal dash

Dash trouble codes
Format is t then code number then history then current some have nu which I cant remember but believe was not used
Eg
t00-- is fuel gauge sender open circuit no history and no current faults
t16h- is abs history codes but no current fault

00 Fuel gauge sender unit — open circuit
01 Fuel gauge sender unit — short circuit
02 Fuel gauge sender unit — intermittent
03 Fuel gauge sender unit — open circuit
04 LPG gauge sender unit — open circuit
05 LPG gauge sender unit — short circuit
06 LPG gauge sender unit — intermittent
08 No serial data from ABS
09 No serial data from BCM
10 No serial data from ECC
11 No serial data from PCM
12 No serial data from SDM
13 No instrument poll from BCM
14 No serial communication
15 No Sub-clock
16 ABS or ABS/ETC fault logged
17 BCM fault logged
18 ECC fault logged
19 PCM fault logged
20 SDM fault logged
21 Trip switch short circuit
22 Trip switch button stuck
24 EE checksum error
25 ROM checksum error
26 Internal fault

 

[muzza73]

Awesome thanks so much for the detailed information

 

[BlackVXGTS]

Most of the cheap scan tools won't do airbag codes. They only do engine and maybe transmission. You need a Tech2 (or equivalent). Envouscustoms have a product that can display VT/VX ABS codes (I think) - check their web site.