Lumina V6-204 3.4L DOHC (1991)
Technical Service Bulletin # 913426E
Date: 910601
Typical Voltages/ECM Connector End View Charts
Number:
91-342-6E
Section:
6E
Date:
JUNE 1991
Corporate Bulletin No.: 116516
Subject:
ADDITIONAL TYPICAL VOLTAGES AND
ECM CONNECTOR END VIEW CHARTS
Model and Year:
1990-91 LUMINA AND CORVETTE
This bulletin updates the following engines and carlines:
1990-1991 2.5L (VIN R) "W" Carline
1990-1991 3.1L (VIN T) "W" Carline
1990-1991 3.4L (VIN X) "W" Carline
1990-1991 5.7L (VIN J) "Y" Carline
1990-1991 5.7L (VIN 8) "Y" Carline
Service Technicians have commented about the inability to read typical voltages in these Electronic Control Module (ECM) Connector End View charts.
These charts are located in Service Manual Section "6E-A", "Driveability And Emissions." This condition has led to development of new charts.
Vehicles equipped with the ECM in the engine compartment require the use of sealed electrical connections. The practice of "backprobing," piercing
insulation, or otherwise breaching the integrity of circuits for diagnostic purposes is strongly not recommended.
The charts may be used in conjunction with the T-100 *Yellow Breakout Box (48921) to obtain voltage values for each circuit listed. Furthermore, if the
voltage is found to be abnormal, the technician may reference the appropriate section, chart, or figure within the service manual to enhance further
diagnosis of the circuit in question.
"We believe T-100 equipment to be reliable. There may be additional manufacturers of such equipment. General Motors does not endorse, indicate any
preference for, or assume responsibility for the products or equipment from those firms or for any such items which may be available from other
sources."
