Roadmaster V8-305 5.0L (1992)
Steering Wheel: All Technical Service Bulletins
Tool Information
A new essential tool (J37608-92) was released in November of 1992 for all Buick dealerships. The new tool consists of three individual jumper
harnesses that work in conjunction with the Steering Wheel Control Adapter (J37608). The tools mentioned above are used in diagnosing Optical
Steering Wheel Control (SWC) systems.
The purpose of the new tools is to allow for isolation of the different Optical SWC components. The purpose of each tool:
J37608 (Steering Wheel Control Adapter) - This tool can connect in parallel to the Cancel Cam Assembly, the E & C Interface Module, the Turn Signal
Switch, and the SWC head or keypad. It allows for voltage measurements to be taken on any of the SWC power, ground, illumination, or data lines.
J37608-92A (Jumper Harness) - This jumper harness connects to the vehicle connector that plugs into the E & C Interface Module. This allows for
Battery, Ground, and the E & C Data line (CKT 835) to be connected to the SWC Adapter; which can power up the SWC head or keypad and the E & C
Interface module. Thus, the Cancel Cam Assembly and Turn Signal Switch can be bypassed and allow for testing of the E & C Interface Module and the
SWC head or keypad.
J37608-92B (Jumper Harness) - This jumper harness allows Data In and Data Out messages to be sent without the Cancel Cam Assembly and the Turn
Signal Switch in the system. When bypassing these components, if the SWC problem disappears; a problem exists with either the Cancel Cam Assembly
or the Turn Signal Switch. If the problem remains, the fault is due to one of the remaining SWC components.
J37608-92C (Jumper Harness) - This jumper harness has a connector similar to the Data Link Connector (DLC) which the TECH 1 can be connected to
and a ground wire which provides proper grounding of the TECH 1. The TECH 1 is used to monitor Entertainment & Comfort (E & C) data messages
that are sent from the SWC head, SWC keypad, and the Radio or to simulate the SWC head or keypad by sending messages through the SWC
components.
Use this revised information in place of the information found in Section 8A-89 of the service manual.
The remainder of this bulletin applies to the Delco Electronics Sound Service Audio Systems Diagnostics Guide.
When using the Sound Service Audio Systems Diagnostics Guide to diagnose optical Steering Wheel Control complaints:
Refer to pages (5-43 - 5-53) for the symptom table and diagnostic charts.
Refer to pages (5-54 - 5-56) for jumper harness connection instructions.
Refer to pages (2-17 - 2-20) for component and circuit descriptions.
Revisions to the Delco Electronics Sound Service Audio Systems Diagnostics Guide.
IMPORTANT:
To avoid misdiagnosis, after selecting the appropriate symptom from the symptom table, refer to these revisions for the appropriate chart.
