Tools - IAC Driver Use Instructions
89pontiac26Bulletin Number: 90-6-12
Reference Number: 916531
Publish Date: 12/89
Subject: USE OF IAC DRIVER TOOL
Models
Affected: 1987-90 6000 AND GRAND PRIX WITH 2.8L AND 3.1L (VIN T,W)
This bulletin is to inform General Motors Dealer Technicians using the Idle Air Control (IAC) Driver Tool "Special Tool" Number (22M - Concept Technology) or (J 37027-A - Kent Moore) on all 2.8L/3.1L MPFI engines that the Diagnostic Test Terminal must be grounded or Field Service Mode entered if a "Scan Tool" is used.
The grounding procedure is fully explained in the diagnostic charts for Service Manual Sections "6E3-A" (Code 35) and "6E3-C2" (Idle Air Control (IAC) Circuit). However, the grounding procedure must also be followed when using the tool for other uses such as: Idle (RPM) Control, Generator Diagnosis, A/C Recharging, etc.
The engine carlines involved are as follows:
1989-1990 "6000 And Grand Prix" Carlines
1987-1988 "6000 And Grand Prix" Mass Air Flow to Speed Density Updates
It should also be noted that whenever the IAC system is disconnected or a battery disconnect is made, the "Idle Learn Procedure" in Section "6E3-C2" of the Service Manual should be followed.