Pgm·fi Troubleshooting Information 6·13 - Honda 2006 TRX680FA Service Manual

FUEL SYSTEM (PGM-FII
PGM-FI TROUBLESHOOTING INFORMATION
GENERAL TROUBLESHOOTING
Intermittent Failure
The term "intermittent failure" means
<I
system may have had a failure. but it checks OK now. If the MIL does not coma on,
check for poor contact or loose pins at all connectors related to the circuit with the trouble. If the MIL was on, but then went
out, the original problem
may
be intermittent.
Opens and Shorts
"Opens" and "Shorts" are common electrical terms. An open is a break in a wire or at a connection. A short is an accidental
connection of a wire to ground or to another wire. In simple electronics, this usually means something will not work at all.
With peMs this can mean something will work, but not the way it's supposed to.
If the MIL has come on
Refer to DTe READ OUT (page 6-14).
If the MIL did not stay on
If the MIL did not stay on, but there is a driveability problem, do the SYMPTOM TROUBLESHOOTING (page 6-5).
SYSTEM DESCRIPTION
SELF-DIAGNOSIS SYSTEM
The PGM-FI system is equipped with the self-diagnostic system. When any abnormality occurs in the system, the peM
turns on the MIL and stores a OTC in its erasable memory,
FAIL-SAFE FUNCTION
The PGM-FI system is provided with a fail-safe function to secure a minimum running capability even when there is trouble
in the system. When any abnormality is detected by the self-diagnosis function, running capability is maintained by pre-
programed value in the simulated program map. When any abnormality is detected in the injector and crankshaft position
(CKP) sensor, the fail-safe function stops the engine to protect it from damage.
OTC (Diagnostic Trouble Codel
• The OTC is composed of a main code and a sub code and it is displayed as a hyphenated number when retrieved from
the PCM with the HOS pocket tester.
The digits in front of the hyphen are the main code, they indicate the component offunction failure.
The digits behind the hyphen are the sub code, they detail the specific symptom of the component or function failure.
For example, in the case ofthe TF sensor:
- DTC 08 -1 .. (TP sensor voltage) - (lower than the specified value)
- DTe
08 - 2
=
(TP sensor voltage) - (higher than the specified value) .
• The MAP, ECT, TP and IAT sensor diagnosis will be made according to the voltage output of the affected sensor.
If
a
failure occurs, the peM determines the Function Failure, compares the sensor voltage output 10 the standard value,
and then outputs the corresponding DTC to the HDS Pocket Tester,
For example:
- If the input voltage line (A) on the MAP sensor is opened, the PCM detects the output voltage is about 5 V, then the
DTC 1-2 (MAP sensor circuit high voltage) will be displayed.
- [f the input voltage line lB) on the TP sensor is opened, the PCM detects the output voltage is 0 V, then the DTC 8·1 (TP
sensor circuit low voltage) will be displayed.
5V
OUTPUT VOLTAGE
---9---¢~-t'-
TP SENSOR
v
TPUTVOLTAGE
5V
MAP SENSOR
-; ~
5
~
}:
(A)
OU
."L
UTPUT VOLTAGE
~O-
5V
IATSENSOR
i
0
."L
OUTPUT VOLTAGE
5V
EeT SENSOR
6-13