Briggs & Stratton BIG BLOCK EFI, Руководство по ремонту

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Section 2: Troubleshooting DTCs 19
DTC P0107/P0108 Manifold Absolute Pressure (MAP) Sensor
Signal Voltage Low, Open or High
Circuit Description
The MAP sensor responds to changes in mani-
fold pressure (vacuum). The ECM receives
this information as a signal voltage that varies
between about 0.5 volts at idle to 4.5 volts at
Wide Open Throttle (WOT).
If the MAP sensor fails, the ECM substitutes a
default MAP value.
The MAP sensor voltage of 5 volts is delivered
to the MAP sensor through ECM terminal J2-
16. The MAP sensor sends a voltage signal
back to the ECM on terminal J2-11 according
to the manifold pressure value on the termi-
nal.
Diagnostic Aids
Check for the following conditions:
1. Poor ECM connection. Inspect wire har-
ness connectors for backed out terminals,
improper mating, broken locks, improperly
formed or damaged terminals, and poor
terminal to wire connection.
2. Damaged wire harness and/or connec-
tors. If harness appears to be OK, shake or
wiggle wire harness and/or connector with
DVOM or ETA connected. Radical voltage
changes or a change in the MAP sensor
display can indicate the location of the fault
condition.
Always clear DTCs after performing repairs.
MAT/MAP
Sensor
ECM
MAT
Sensor
Signal
3
J2 08
TAN/BLACK
4
5 Volt
Return
J2 10
BROWN
MAP
Sensor
Signal
1
J2 11
WHITE/RED
5 Volt
Reference
2
J2 16
RED/WHITE