Mahindra Quanto - HFM Sensor Troubleshooting; P0103: HFM Sensor Signal Range Check

DIAGNOSTIC MANUAL MAN-00201
QUANTO EMS SEP 2012/Rev 1
The repair methods given by the manufacturer in this document are based on the technical specifications, current at the time of release. The methods may be modified as a result of changes introduced by the
manufacturer in the production of the various component units and accessories from which the vehicles are manufactured. The reproduction, translation, transmission, in part of or whole of the present document,
are prohibited without the prior written consent of Mahindra & Mahindra Ltd. The use of this document by any person other than the trained personnel, at the Authorized Service Centre of Mahindra & Mahindra Ltd.,
will amount to unauthorized use and shall be liable for penalty/prosecution© 2012 Mahindra & Mahindra Ltd.
`
P0103 SIGNAL RANGE CHECK FOR HFM7 SENSOR SIGNAL ABOVE MAXIMUM LIMIT
HFM SENSOR
Mass air flow rate is measured by detection of heat transfer from a hot film probe.Because of the change
of the mass air flow rate causes change in the amount of heat being transferred from the hot film probe
surface to the air flow. The airflow sensor generates a pulse so it repeatedly opens and closes between
the 5V supplied from the engine control module. This results in the change of the temperature of the hot
film probe and in turn change of resistance.
DTC INFORMATION PROBABLE CAUSES OF FAILURE
NORMAL OPERATION
 Ignition ON
 The HFM sensor outputs a voltage, which corresponds to the
intake airflow.
 The ECU checks whether this voltage is within a specified
range.
DTC DETECTING CONDITIONS
 Ignition ON
 EMS ECU supply voltage 8-16V
 The measured output voltage of the sensor is more than
5.25 V for few second s
DTC REACTIONS
 OBD check lamp will be continuously ON.
 EGR Switches OFF.
.
HEALING CONDITION
 Ignition Off/On
 HFM (air mass) signal wire
short to battery
 HFM sensor internal failure
 Failed EMS ECU
22