Using F3-D heavy truck diagnostic tool solve Man Engine poor acceleration

Using F3-D heavy truck diagnostic tool solve Man
Engine poor acceleration
MAN Vehicle mode: MAN
Date of manufacture: June, 2000
Driving : 645201KM
VIN:WMAT31ZZZYM303495
Fault phenomenon: This vehicle dirving powerless, engine unable to
accelerate, EDC light on.
Fault diagnosis: This vehicle is electronic control system, to diagnose
with Fcar F3-D heavy duty scanner,connect testing cable to test head and
main unit respectively,(diagnostic plug is above relay box besides center
console).
Diagnostic socket
Pic.1 Diagnostic socket position
In the case of without 37-pin diagnostic connector,you can use jumper box
to connect and diagnose.Jumper method see table 1,connect testing cable
respectively with jumper box and main unit of F3-D heavy truck diagnostic
tools.Turn ignition switch to ON gear position,swtich on power switch of
Fcar heavy duty truck tools.Entry to menu 【Diesel】—【MAN】—【V5.3】
—【BOSCH EDC MS5/M(S)5】—【Read DTC】,Fault display ”87 intake pressure
sensor fault””85 coolant temperature sensor fault” 【Clear DTC】
display“System clear success”in【Read DTC】“87 intake pressure
sensor”“85 coolant temperature sensor”appear again,DTC cannot be
cleared Selct menu【Read data stream】on menu and click to enter and
check(Readout data see Table 2).To analyze the specific faulty part
combining with data stream.

Sensor name
High speed Idle Static
Water temperature sensor° 95 95 95
Inlet pressure sensor kpa 120 120 120
Engine speed rpm 1900 730 0
Table 1 Connection of Jumper box with diagnostic socket
Fault Analysis
Pic.1 Engine coolant temperature sensor
To analyze according to reading data stream, the vehicle engine still cold
water temperature sensor data stream is 95 degrees, the intake pressure
sensor data 120kPa. Start the engine, after idle for some time no change
in water temperature data, depresses the accelerator pedal to increase
engine speed, view the data stream, intake air pressure sensor data is
still 120kpa unchanged, indicating that the water temperature sensor and
intake air pressure sensor data is abnormal (see data stream of this
vehicle in Table 2, Table 3 are data stream that has some changes),
initially judge water temperature sensor and intake air pressure sensor
part is defective.
Pic.2 Engine coolant temperature sensor
Check water temperature sensor and intake air pressure sensor, both of
which were found abnormal, to be replaced.
Sensor name
High speed Idle Static
Water temperature sensor° 95 95 95
Inlet pressure sensor kpa 120 120 120
Engine speed rpm 1900 730 0

Inlet pressure sensor position
Table 2 data stream of this vehicle
Water temperature sensor 85 85
Pic. 3
Inlet pressure
sensor position
28
Inlet pressure sensor kpa 600 200 100
Engine speed rpm 1900 730 0
Table 3 changed data stream
Troubleshooting
Replace water temperature sensor see Pic.2,inlet pressure sensor see
Pic.3.Use menu on Fcar truck diagnostic tools menu to clear DTC,display
clear success,Read DTC,system normal,road test,fault
disappear,completely remove fault.