Honda 2004 Odyssey, Service Manual

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PCM Data
Data Description Operating Value Freeze Data
11-11
You can retrieve data from the PCM by connecting the OBD II scan tool or HDS to the data link connector (DLC). The
items listed in the table below conform to SAE recommended practice. The HDS also reads data beyond that
recommended by SAE to this data may help you find the causes of intermittent problems.
NOTE:
• The ‘‘operating values’’ listed are approximate and may vary depending on the environment and the individual
vehicle.
• Unless noted otherwise, ‘‘at idle speed’’ means idling with the engine completely warmed up, the transmission in
park or neutral, and the A/C and all accessories turned off.
Diagnostic
Trouble Code
(DTC) If the PCM detects a problem, it will store it as a code
consisting of one letter and 4 numbers. Depending on the
problem, as SAE-defined code (P0xxx) or a Honda-defined
code (P1xxx) will be output to the tester. If no problem is
detected, there is no
output. YES
Engine Speed The PCM computes engine speed from the signals sent
from the Crankshaft Position (CKP) sensor. This data is
used for determining the time and amount of fuel
injection. Nearly the same as
tachometer
indication
At idle speed: 730
50 rpm YES
Vehicle Speed The PCM converts pulse signals from the output shaft
(countershaft) speed sensor into speed data. Nearly the same as
speedometer
indication YES
Manifold
Absolute
Pressure (MAP) The absolute pressure caused in the intake manifold by
engine load and speed. With engine stopped:
Nearly the same as
atmospheric
pressure.
At idle speed: about
20
34 kPa (150
260 mmHg, 6 10
in.Hg), 0.9 1.1 V
YES
Engine Coolant
Temperature
(ECT) The ECT sensor converts coolant temperature into voltage
and signals the PCM. The sensor is a thermistor with
internal resistance that changes with coolant temperature.
The PCM uses the voltage signals from the ECT sensor to
determine the amount of injected fuel. With cold engine:
Same as ambient
temperature and IAT
With engine warmed
up: about 176
212°F
(80 100°C), 0.5
0.7 V
YES
Primary Heated
Oxygen Sensor
(Primary HO2S)
(Sensor 1),
Secondary
Heated Oxygen
Sensor
(Secondary
HO2S)
(Sensor 2) The HO2S detects the oxygen content in the exhaust gas
and sends voltage signals to the PCM. Based on these
signals, the PCM controls the air fuel ratio. When the
oxygen content is high (that is, when the ratio is leaner
than the stoichiometric ratio), the voltage signal is lower.
When the oxygen content is low (that is, when the ratio is
richer than the stoichiometric ratio), the voltage signal is
higher. 0.0 1.25 V
At idle speed:
about 0.1
0.9 V
(cont’d)
03/07/29 09:17:47 61S0X050_110_0011