Assuming you have the battery cables clean and tight and didnt blow any maxi fuses or fusible links.......there is a TSB (Technical Service Bulletin) that may apply to your concern.
Worth looking into....
Bulletin No.: 01-08-45-005E
Date: August 29, 2006
Hard/No Start, Fuel Gauge Inoperative/Fluctuates, SES/Check Engine Light On, ABS Warning Light On, TCS Warning Light On, TCS Activation, Service Traction System Message Displayed, All-Wheel Drive Disable Message Displayed, DTCs Set (Repair Connector)
2002-2006 Buick Rendezvous
2005-2007 Buick Terraza
2000-2005 Chevrolet Venture
2005-2007 Chevrolet Uplander
2000-2004 Oldsmobile Silhouette
2000-2005 Pontiac Montana
2001-2005 Pontiac Aztek
2005-2007 Pontiac Montana SV6
2005-2007 Saturn Relay
This bulletin is being revised to add 2007 model year. Also, additional information was added to the Important statement. Please discard Corporate Bulletin Number 01-08-45-005D (Section 8 - Body and Accessories).
Some customers may comment on one or more of the following conditions:
Engine is hard to start
Engine will not start
Engine starts then stalls
Fuel gauge is inoperative or fluctuates
Service Engine Soon/Check Engine light is illuminated
ABS Warning Light is illuminated
TCS Warning Light is illuminated
Service Traction System message displayed
All-Wheel Drive Disable message displayed
These conditions may be intermittent. Upon investigation, the technician may find various DTCs set.
This condition may be due to water leaking into the interior of the vehicle, and/or spread terminals, at connector C305 that is located on the floor to the rear of the driver's seat. This connector is not sealed from the inside of the vehicle and water may enter the connector causing the terminals to become corroded. Also, the female terminals of the connector may have become spread apart causing an intermittent poor connection.
Inspect the terminals at connector C305 for corrosion or spreading before replacing the fuel module or resistor card kit. Terminals can be accessed from underneath the vehicle.
Do not attempt to repair any spread female terminals as this will result in a return repair. The female terminal must be replaced.
If the terminals show signs of corrosion, determine the source of the water leak first and repair the water leak before repairing the terminals in connector C305. Refer to Corporate Service Bulletin Number 01-01-38-009A to determine a potential source for water in the vehicle interior.
Hope this helps
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