INTERMITTENT TCC, NO TCC OR CODE 62/26 - SES LIGHT

MODELS AFFECTED: 1987-90 MODELS EQUIPPED WITH HYDRA-MATIC 3T40 (THM 125C)

BULLETIN COVERS:

A New Spiraled Roll Pin used in the 2nd Gear Switch (338) replaces the previous split roll pin, which may become loose and fall out of the switch, causing possible intermittent and/or no TCC, Service Engine Soon Light, and/or Code 62 and/or Code 26.

DATE OF PRODUCTION CHANGE:

The 2nd gear switch has a three (3) digit code stamped on top of the switch (metal side). The first two (2) digits in the code represent the week in which the switch was built; the 3rd digit represents the calendar year. All switches built with number Date Stamp 429 (November 29, 1989) and after will contain the new spiraled roll pin. (Figure 1)

2nd Gear switches equipped with new spiraled roll pins went into production in all Hydra-Matic 3T40 (THM 125C) transaxles on Julian Date 333 (November 29, 1989).

SERVICE PROCEDURE:

Do not attempt to repair suspect gear switches equipped with split roll pins. If an inoperative 2nd gear switch is found in any Hydra-Matic 3T40, (THM 125C) replace it with a new one.

SERVICE PARTS INFORMATION:

Part Number Description ----------- ----------- 8664388 Switch, 2nd Gear

Parts are currently available from GMSPO.

SERVICE MANUAL REFERENCE:

Whenever replacing a 2nd gear switch on any Hydra-Matic 3T40, (THM 125C) refer to the Unit Repair Section of your Service Manual.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.