For 1990-2009 cars

Notice: If the vehicle has been exposed to extensive water intrusion, such as water leaks, window left open, driving through high water and so forth, the Sensing and Diagnostic Module (SDM) and the SDM connector may need to be replaced. With the ignition OFF, inspect the area under the front seat and the area around the SDM, including the carpet. If any significant soaking or evidence of significant soaking is detected, the water must be removed, water damage repaired and the SDM and the SDM connector MUST be replaced. Before attempting any of these repairs, the SIR system must be disabled. Refer to SIR.

GM vehicles are designed in order to operate under normal environmental conditions. Sealing materials and components are designed in order to withstand the natural elements. These specifications cannot take into consideration artificial conditions, such as high-pressure car washes.

The watertest procedure performs the following functions:

• | Relates to the natural elements

• | Determines the ability of a vehicle to perform under normal operating conditions

Repairing body waterleaks is a combination of proper testing, diagnosis, and the following types of repair:

• | Adjustment of misaligned components

• | Application of proven repair materials

The first step in the waterleak diagnosis is finding the conditions under which the leak occurs. Refer to the following examples:

• | The leak occurs only when the vehicle is parked on an inclined drive.

• | Water appears in the spare tire apartment.

If you can find the general leak area, you may quickly isolate the exact entry point by the use of a localized test, such as a water hose or an air hose.

If the leak source is not obvious, use the generalized testing method, using watertest equipment such as watertest stands. Refer to Generalized Testing . You may have to remove some interior trim panels or some components in order to confirm repairs.