Abs cel lights and gas gauge

[FISH96]

2002 malibu 3.1 litre 101,000 aprox.
Gas gauge goes to empty, abs light illuminates, cel illuminates. These are intermittent. There seems to be no other indications of trouble. Automobile runs, restarts without incident, except for the above.
Received this info over the phone.

I have not had the chance to check dtc's or to look for the obvious.

The unit has had bcm replaced at 75k, along with a pcm reflash.
It also suffered from the security light issue which was overcome with the resistor installation following ponchonutty's instruction (this forum). This was done about 1 year ago. Battery is 2 years old, serpertine belt is ok. An underhood visual is done once per week.

Anyone have any ideas? When i arrive back from a road trip ( another car) i will look for codes and alternator malfunction.

Thank you in advance for any thoughts,
fish 96

[gmtech1]

Post codes when you can.

[FISH96]

No DTCs present, cannot duplicate the condition either. Not capable of retrieving ABS codes. I reason if engine DTCs are not present ABS codes are not present either.

I am favoring some sort of electrical snafu which can be very evasive. Basing this on the action of the gasoline gauge.

Tightened battery terminals, feed lug to power distributon fuse box as well as main ground lug front of engine.
Went on another road test nothing amiss.

Will anyone give me the location of the Body Control Module under the dash and how to ID the contraption. It has been previously replaced by a repair shop for a myriad of other problems about 71k miles. Just want to make sure there is no loose/dirty connections.
The prior BCM was very corroded. Perhaps there is a small leak that I am unaware. The floor rugs are dry.
Regards,
Fish96

[gmtech1]

First off, don't assume there are no ABS codes, need to have them checked with a capable scanner. The BCM is under the right side of the dash, attatched to a bracket that is bolted to the HVAC housing. It has three connectors.

[FISH96]

Thank you for the reply. Upon further interrogation of the driver during the incidents, found it is not the CEL/MIL but the Service Vehilce Soon light that became illuminated with the ABS and gas gauge malfunction.
From what I understand this is a horse of a different color.
I will not have a chance to delve into this until much later in the week.

Any help with this particular light would be appreciated.
Owner's manual states fault in Day time Running Lights DRL or Automatic Light Control (ALC) will light the Service Engine Soon light.

FISH96

[gmtech1]

You need to have the vehicle scanned with a capable scanner that will check ABS and BCM codes. Then start the diag.