NEXON DIAGNOSTIC MANUAL

OSPREY- Application

DTC Troubleshooting Data

Version: 4.0

Date: 10-02-2017

Prepared by: Mithipati Prasad

Checked by: G S Raju / Senthilnathan S

Page: 44 of 654

TATA MOTORS Ltd.

This document must not be used in any way, such as copying and redistributing to third parties, without the consent of author.

P0087: Rail pressure low during cranking

Overview:

DTC Description as per ISO

standard

Fuel Rail/System pressure - Too low

ECU Pin Number

Customer Symptom

Engine may not start if Engine turns Off

Power loss due to Engine torque restriction.

Fuel Efficiency will improve and Nox emissions will increase.

Fault Effects (On Vehicle)

EGR does not function/EGR disable

Engine may not start

Lamp Status (If Any)

CE and MI lamp is ON.

Fault Detection Condition

This DTC gets logged if no rise in rail pressure is detected even after 6

seconds of cranking.

Normal Operating Condition

No Faults related to Rail Pressure sensor

Probable Trouble Area

Rail pressure sensor, ECU, Wiring harness

Healing Condition

Clear the errors, Ignition OFF to ON, Crank the engine, engine idle, fly-up

and specially vehicle running in different speed condition. (1 driving cycle

after fault rectification)

Component Details:

Rail pressure sensor is a piezoelectric type one, which is used to measure the fuel pressure inside the Rail. It provides the

pressure in terms of voltage to the ECU. This rail possesses an under pressure supply of diesel fuel which is ready to be

used by the injectors. The drop of pressure in the rail is immediately signaled by the sensor to the engine control unit. This

is followed by the restoration of pressure in the pump. It is the engine control unit that controls the fuel supply of the rail

from a pump possessing very high pressure. This is done by using a valve for controlling the pressure of fuel.

Preliminary Checks

Check whether the customer voice / view about the issue is matching with the fault effects mentioned above. If

yes, go ahead with next steps. If not, check for other DTC’s presence.

Check whether similar complaints are earlier reported. If yes, perform the preliminary checks with respect to

earlier issue closure.

Check adequate fuel is available in the tank.

Check ECU pins and connector, replace if found defective.

Check HP circuit; Refer HP circuit check and rectification procedure.

Check LP circuit; Refer LP circuit check and rectification procedure.

Check the EMS and Rail Pressure sensor connectors for pin back out / damage. If found, then Rectify the issue.

Also check for oxidation of pins.