09-018-13-2803

Service Bulletin
Mazda North American Operations
Irvine, CA 92618-2922
© 2013 Mazda Motor of America, Inc.
Subject:
Bulletin No:
09-018/13
Last Issued:
06/04/2013
DISPLAY SHOWS INACCURATE AMBIENT TEMPERATURE
MULTI-MODEL - DISPLAY SHOWS INACCURATE AMBIENT TEMPERATURE
BULLETIN NOTE
• This bulletin supersedes the previous bulletin 09-015/11, issued on 06/13/2011. The APPLICABLE
MODEL(S)/VINS and DESCRIPTION have been revised.
• Changes are noted below in Red beside the change bar.
APPLICABLE MODEL(S)/VINS
2011-2013 Mazda2
2003-2014 Mazda6
2007-2013 Mazda CX-9
2004-2014 Mazda3
2013-2014 Mazda CX-5
2009-2013 Mazda MX-5
2012-2013 Mazda5
2007-2012 Mazda CX-7
2004-2011 Mazda RX-8
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.
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 MS3 online or Workshop Manual (section 09-22 AMBIENT TEMPERATURE SENSOR
INSPECTION).
Replace the sensor only when it fails the Workshop Manual inspection.
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CONSUMER NOTICE: The information and instructions in this bulletin are intended for use by skilled technicians. Mazda technicians utilize the proper tools/
equipment and take training to correctly and safely maintain Mazda vehicles. These instructions should not be performed by “do-it-yourselfers.” Customers
should not assume this bulletin applies to their vehicle or that their vehicle will develop the described concern. To determine if the information applies,
customers should contact their nearest authorized Mazda dealership. Mazda North American Operations reserves the right to alter the specifications and
contents of this bulletin without obligation or advance notice. All rights reserved. No part of this bulletin may be reproduced in any form or by any means,
electronic or mechanical---including photocopying and recording and the use of any kind of information storage and retrieval system ---without permission in
writing.
Bulletin No: 09-018/13
Last Issued: 06/04/2013
© 2013 Mazda Motor of America, Inc.
CONTROL LOGIC OF AMBIENT TEMPERATURE
• The ambient temperature display is NOT always equal to the reading of the temperature sensor 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
Condition
Display temperature
Low engine temp
Actual sensor reading
High engine temp
The last temperature recorded when
IG was off
Note:
The threshold of the engine temp
differs depending on car model, but it
is approx. 122-140°F (50-60°C)
Note
Especially in summer, display may
show false high temperature due to
heat from street.
Reason for adjustment
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
Condition 3 - Ambient temperature change
Condition
Low ambient temp
Display temperature
Gradually changes to actual sensor
reading
Note
When moved from garage/indoor
parking lot to outside, it may take long to
show actual ambient temperature.
Reason for adjustment
Under certain conditions, the sensor
reading is adjusted in order to avoid
false reading.
High ambient temp
Immediately changes to actual sensor
reading
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Bulletin No: 09-018/13
Last Issued: 06/04/2013
© 2013 Mazda Motor of America, Inc.
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 the temperature around the vehicle.
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