09018173351

Technical
Service Bulletin
Mazda North American Operations
Irvine, CA 92618-2922
Subject:
09-018/17 - DISPLAY SHOWS INACCURATE AMBIENT
TEMPERATURE
Bulletin No.: 09-018/17
Last Issued: 05/22/2017
BULLETIN NOTES
This bulletin supersedes the previously issued bulletin(s) listed below: The changes are noted in Red.
Previous TSBs: Date(s) Issued:
09-023/14
05/20/2014
09-018/13
06/04/2013
09-015/11
06/13/2011
APPLICABLE MODEL(S)/VINS
2011-2017Mazda2 2003-2017Mazda6
2007-2012 Mazda CX-7 2004-2011 Mazda RX-8
2004-2017Mazda3 2016-2017Mazda CX-32007-2017Mazda CX-9
2012-2017Mazda5 2013-2017Mazda CX-52009-2017Mazda MX-5
DESCRIPTION
Some customers may complain that the ambient temperature display is not accurate, or it takes too long for
the display to show actual temperature.
Page 1 of 3
CONSUMER NOTICE: The inf ormation and instructions in this bulletin are intended f or use by skilled technicians. Mazda technicians utilize the proper tools/
equipment and take training to correctly and saf ely maintain Mazda v ehicles. These instructions should not be perf ormed by “d o-it-y ourself ers.” Customers
should not assume this bulletin applies to their v ehicle or that their v ehicle will dev elop the described concern. To determine if the inf ormation applies,
customers should contact their nearest authorized Mazda dealership. Mazda North American Operations reserv es the right to alt er the specif ications and
contents of this bulletin without obligation or adv ance notice. All rights reserv ed. No part of this bulletin may be reproduced in any f or m or by any means,
electronic or mechanical---including photocopy ing and recording and the use of any kind of inf ormation storage and retriev al sy stem ---without permission in
writing.
© 2017 Mazda North American Operations, U.S.A.
Bulletin No.: 09-018/17
Last Issued: 05/22/2017
When you encounter a customer with this concern, first verify the condition when the customer noticed this
symptom. If the condition is similar to the following "CONTROL LOGIC OF AMBIENT TEMPERATURE" or
"DIFFERENCE BETWEEN THE TEMPERATURE DISPLAY AND OTHERS", advise the customer that this
is a normal characteristic of the vehicle and not a malfunction.
If the condition does not meet the following and the sensor malfunction is suspected, make sure to inspect
the sensor according to MGSSonline or Workshop Manual (section 09-22 AMBIENT TEMPERATURE
SENSOR INSPECTION).
Replace the sensor only when it fails the Workshop Manual inspection.
CONTROL LOGIC OF AMBIENT TEMPERATURE




The ambient temperature display is NOT always equal to the reading of the temperature sens or
mounted in front of the vehicle.
Under certain conditions, the sensor reading is adjusted in order to avoid false high reading due
to heat from engine and/or road surface.
The ambient temperature display is adjusted during the following conditions shown below.
Due to this adjustment, the temperature on the display may temporarily differ from actual.
EXAMPLE OF CONDITIONS WHEN SENSOR READING IS ADJUSTED
Condition 1 - Engine coolant temp when ignition switch (IG) is on
Low engine
Condition
High engine temp
temp
Display
Actual sensor
The last temperature recorded when IG was off
temperature
reading
Note: The threshold of the engine temp differs depending on car
Note
model, but it is approx. 122-140°F (50-60°C)
Reason for
Especially in summer, display may show false high temperature due to
adjustment
heat from street.
Condition 2 - Vehicle Speed
Condition
Low vehicle speed
Display
temperature
The last temperature recorded
Note
The threshold of the vehicle speed differs depending on car model, but
it is approx. 3-15mph (5-25km/h)
High vehicle
speed
Actual sensor
reading
Page 2 of 3
CONSUMER NOTICE: The inf ormation and instructions in this bulletin are intended f or use by skilled technicians. Mazda technicians utilize th e proper tools/
equipment and take training to correctly and saf ely maintain Mazda v ehicles. These instructions should not be perf ormed by “do-it-y ourself ers.” Customers
should not assume this bulletin applies to their v ehicle or that their v ehicle will dev elop the described concern. To determi ne if the inf ormation applies,
customers should contact their nearest authorized Mazda dealership. Mazda North American Operations reserv es the right to alter the specif ications and
contents of this bulletin without obligation or adv ance notice. All rights reserv ed. No part of this bulletin may be r eproduced in any f orm or by any means,
electronic or mechanical---including photocopy ing and recording and the use of any kind of inf ormation storage and retriev al sy stem ---without permission in
writing.
© 2017 Mazda North American Operations, U.S.A.
Bulletin No.: 09-018/17
Last Issued: 05/22/2017
Condition 3 - Ambient temperature change
Condition
Low ambient temp
High ambient temp
Display
Immediately changes to
Gradually changes to actual sensor reading
temperature
actual sensor reading
When moved from garage/indoor parking lot to outside, it
Note
may take long to show actual ambient temperature.
Reason for
Under certain conditions, the sensor reading is adjusted in
adjustment
order to avoid false reading.
NOTE:


When M-MDS is connected, the ambient temperature shown on M-MDS is the actual
temperature sensor value; however, in some cases, it may not match the instrument cluster
display because the value may be adjusted. Do NOT attempt repair due to this difference.
If temperature sensor connector is disconnected then connected, the recorded temperature is
lost and the display starts to show actual sensor reading regardless of the condition.
Sometimes it is misjudged that the symptom is fixed by the sensor replacement, but actually,
the display has reset and now shows actual sensor reading because the connector was
disconnected. So the sensor is not the root cause.
DIFFERENCE BETWEEN THE TEMPERATURE DISPLAY AND OTHERS
If the vehicle’s temperature display does not match an external temperature display (such as a bank sign
showing outside temperature), this is because the external temperature display does not always show th e
temperature around the vehicle.
Page 3 of 3
CONSUMER NOTICE: The inf ormation and instructions in this bulletin are intended f or use by skilled technicians. Mazda technicians utilize th e proper tools/
equipment and take training to correctly and saf ely maintain Mazda v ehicles. These instructions should not be perf ormed by “do-it-y ourself ers.” Customers
should not assume this bulletin applies to their v ehicle or that their v ehicle will dev elop the described concern. To determi ne if the inf ormation applies,
customers should contact their nearest authorized Mazda dealership. Mazda North American Operations reserv es the right to alter the specif ications and
contents of this bulletin without obligation or adv ance notice. All rights reserv ed. No part of this bulletin may be r eproduced in any f orm or by any means,
electronic or mechanical---including photocopy ing and recording and the use of any kind of inf ormation storage and retriev al sy stem ---without permission in
writing.
© 2017 Mazda North American Operations, U.S.A.