Boost pressure sensor circuit high
The signal wire is seeing more voltage than the circuit should ever produce — usually the signal wire touching battery power or the 5 V reference.
SPN 102 — Boost pressure sensor circuit high
SPN 102 is the parameter the ECM is flagging on PACCAR, CAT, Detroit, International, MERCEDES, Volvo, Mack, Cummins engines. The FMI that comes with it tells you how it failed. Each failure mode below has its own causes and its own test order — do not treat them as the same repair.
Boost pressure sensor circuit voltage below normal
The signal is pinned low — usually the signal wire touching ground, or the 5 V reference lost.
Boost pressure sensor circuit voltage below normal
The signal is pinned low — usually the signal wire touching ground, or the 5 V reference lost.
Boost pressure sensor circuit voltage below normal
The signal is pinned low — usually the signal wire touching ground, or the 5 V reference lost.
Boost pressure sensor circuit voltage below normal
The signal is pinned low — usually the signal wire touching ground, or the 5 V reference lost.
Boost pressure sensor circuit voltage below normal
The signal is pinned low — usually the signal wire touching ground, or the 5 V reference lost.
Boost pressure sensor circuit voltage below normal
The signal is pinned low — usually the signal wire touching ground, or the 5 V reference lost.
Boost pressure sensor circuit voltage below normal
The signal is pinned low — usually the signal wire touching ground, or the 5 V reference lost.
Boost pressure sensor circuit voltage below normal
The signal is pinned low — usually the signal wire touching ground, or the 5 V reference lost.
Boost pressure above normal - moderately severe
Real reading, clearly high. Usually the middle warning stage before a derate.
Boost pressure above normal - moderately severe
Real reading, clearly high. Usually the middle warning stage before a derate.
Boost pressure above normal - moderately severe
Real reading, clearly high. Usually the middle warning stage before a derate.
Boost pressure above normal - moderately severe
Real reading, clearly high. Usually the middle warning stage before a derate.
Boost pressure above normal - moderately severe
Real reading, clearly high. Usually the middle warning stage before a derate.
Boost pressure above normal - moderately severe
Real reading, clearly high. Usually the middle warning stage before a derate.
Boost pressure above normal - moderately severe
Real reading, clearly high. Usually the middle warning stage before a derate.
Boost pressure above normal - moderately severe
Real reading, clearly high. Usually the middle warning stage before a derate.
The reference is free. The diagnosis is Pro.
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