Park/Neutral Contact And Fluid Temp Sensor - ATSG 722.6 Service Manual

ELECTRONIC COMPONENTS (CONT'D)
Transmission Fluid Temperature Sensor
The Transmission Fluid Temperature (TFT) sensor is
located in, and part of, the electrical conductor plate,
as shown in Figure 17. Its purpose is to measure the
fluid temp and pass that information to the TCM as an
input signal. The TFT sensor is wired in series with
the Park/Neutral contact.
signal is transferred to the TCM only when the dry-
reed contact of the Park/Neutral contact is closed,
when in Reverse or a forward gear position. In Park
or Neutral the TCM uses engine temperature to avoid
setting a DTC. Refer to the chart in Figure 18 to check
the TFT using either voltage or resistance.
Note: If check is being made at the TCM, shift lever
must be in Reverse or Drive, as engine temp
is used in Park and Neutral.
18
Technical Service Information
The fluid temperature
tft sensor and p/n contact
Figure 17
AUTOMATIC TRANSMISSION SERVICE GROUP
Park/Neutral Contact
The Park/Neutral Contact is located in, and part of,
the electrical conductor plate with the plunger
protruding, as shown in Figure 17. Its purpose is to
transfer information to the TCM as to when the
selector lever is in the "P" or "N" positions. When in
"P" or "N" the P/N contact is acuated by the inside
detent plate. The permanent magnet is moved away
from the dry-reed contact. The dry-reed contact is
opened, and the TCM recieves an electrical signal that
will close the signal to the starter circuit. Cut-Away
of the P/N Contact is shown in Figure 17.
Electronic Components
Continued on Page 19
DRY-REED
CONTACT
PERMANENT
MAGNET
ELECTRICAL
CONDUCTOR
PLATE
PLUNGER
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