1236 / 1575
SAFARI 400NM
SR
NO
DTC
FTB
DESCRIPTION
CAUSES
EFFECT ON VEHICLE
CHECK
POINTS
CORRECTIVE ACTION
MIL
STATUS
CEL
45
P0191
84
Signal Below Allowable
Range
This fault gets logged If the difference
between the rail pressure demand and
the rail pressure feedback is less than a
calibrated minimum threshold for rail
pressure.
1.
EMS ECU disables cruise control
function
1.
Check 30A fuse connected to EMS power relay and battery
(+ve) power supply is not blown off . Replace if required.
2.
Check electrical continuity between ECU pin no A38, A35 &
A19 to Rail pressure sensor connector no 3 ,1, 2. Check
whether the rail pressure sensor signal pin A35 is either
shorted to battery/ground. If so then rectify the wiring harness
connections to make them inline with circuit schematics.
3.
Check electrical continuity of wiring harness between ECU pin
A77 and IMV connector pin 2 & EMS main relay supply and
IMV connector pin 1. rectify wiring harness connections in
case of any issue.
4.
check whether the IMV control pin of EMS A77 is short circuited
to ground/battery because of wrong wiring harness
connections. If so rectify the wrong connections to make the
connections inline with circuit schematics.
5.
Check IMV internal resistance whether it is according to the
design specifications(5.3 ohms at 20 degrees C). Replace
IMV if the resistance is not according to specifications.
6.
Check whether adequate fuel level is available in the tank.
7.
Check high pressure fuel lines for leakage.
8.
Check fuel filter is not clogged.
9.
Check low pressure fuel lines for air entry.
10.
Check & ensure IMV and railpressure sensor connectors for
proper fitment.
11.
Check rail pressure sensor for oxidation, rust etc, if observed
clean deposit.
12.
Check harness for damages; Replace / Repair if harness is
damaged.
13.
Check ECU pins and connector, Replace if found defective.
14.
If vehicle is unable to start the perform 'Static injector back
leak test', Please check if any injector back leak is abnormaly
high compared to other injectors, then replace corresponding
injectors.
15.
If vehicle is able to start then start the vehicle and perform
'Dynamic IMV test' - If test result shows IMV is faulty then
replace IMV.
16.
If vehicle is able to start then start the vehicle and perform
'Dynamic injector back leak test', Please check if any injector
back leak is abnormaly high compared to other injectors, then
OFF
ON