S15/T15 Jimmy 2WD L4-119 1.9L VIN A 2-BBL (1983)
Technical Service Bulletin # 8396
Date: 831201
Oil Pressure Switch - Information
Number:
REISSUE 83-96
Section:
7A (VIIc)
Date:
Dec., 1983
Subject:
OIL PRESSURE SWITCH INFORMATION
Model and Year: ALL THM 700-R4
TO:
ALL CHEVROLET DEALERS
This bulletin is reissued to cover part number changes, part number identification color code revisions, and graphic illustration revisions. Bulletin 83-96
dated October, 1983 should be destroyed.
FIGURE 1 - FOUR SWITCH LOCATIONS
The THM 700-R4 transmission has four (4) oil pressure switch locations in the control valve assembly (see Figure 1).
Depending on vehicle type, various oil pressure switches will be used in these locations. When no switch is used, a 1/8 inch NPT pipe plug, P/N 444612,
is installed in place of the switch.
On vehicles built without an electronic control module (ECM) these switches control the torque converter clutch
operation and exhaust gas recirculation (EGR) bleed system. On ECM equipped vehicles these switches help supply information to the ECM about the
transmission operation. The ECM also controls various functions including fuel mixture, engine timing, engine idle, and torque converter clutch (TCC)
operation. If switches are wrong, mislocated, or malfunction, various electrical and mechanical problems may result, i.e., blown fuses, instrument panel
lights remaining on without apparent reason, or improper engine operation.
General Switch Information
Oil pressure switches are activated by hydraulic pressure from the control valve assembly. Depending on design, a switch may function as the ground for
an electrical circuit or as a simple connecting switch. All switches are designed to be either normally open (N.O.) or normally closed (N.C.).
N.O. - Means the switch will not allow electric current to flow until the switch is activated by hydraulic pressure.
N.C. - Means the switch will allow electric current to flow until the switch is activated by hydraulic pressure.
