AEM Wideband Failsafe Gauge 304900 User Manual

AEM Performance Electronics 
2205 126th Street Unit A, Hawthorne, CA. 90250 
Phone: (310) 484-2322 Fax: (310) 484-0152 
http://www.aemelectronics.com 
Instruction Part Number: 10-4900 Rev B 
 2012 AEM Performance Electronics 
       
Instruction Manual 
P/N 30-4900 Wideband Failsafe Gauge 
 
   
Wideband Failsafe Gauge Parts List 
 
This product is legal in California for racing vehi cles only and should never be used on public highwa ys. 
 
WARNING: 

 ! 
This installation is not for the electronic...

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GETTING STARTED 
  
THIS PRODUCT DOES NOT INCLUDE SOFTWARE IN THE PACKA GING. PLEASE DOWNLOAD 
AND INSTALL THE WIDEBAND FAILSAFE CONFIGURATION SOF TWARE FROM THE AEM 
WEBSITE AT: 
www.aemelectronics.com/downloads 
  
Alternatively, register on the AEM Electronics Foru ms at 
http://forum.aempower.com/forum/index.php  
Click on the All Software & Firmware Downloads  forum. Click on the AEM W ideband Failsafe Software 
link to reach the download page.  The most recent s oftware revision will be...

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Overview 
  
AEM W ideband Failsafe is an advanced safety device that allows the end user to closely monitor the 
performance of their engine.  As a tuning tool, thi s device provides the ability to accurately monitor  AFR, 
while actively protecting the engine by constantly  recording AFR curves and activating a user-defined 
failsafe strategy if it runs dangerously lean or ex cessively rich. 
   
The Wideband FAILSAFE Gauge is a UEGO (Universal Ex haust Gas Oxygen) controller with an internal...

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Installation 
 
1.  Disconnect the negative battery cable.   
2.  Temporarily install gauge without bracket into d esired mounting location.  Gauge mounts into a 2-1/ 16” 
(52MM) hole.  The supplied rubber band can be used  as a spacer around the gauge if it fits loosely in 
mounting hole. 
 
3.  Locate a suitable place in the exhaust system to  install the included oxygen sensor weld bung. On non-
turbocharged engines, mount the oxygen sensor in th e exhaust system at least 18 inches...

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5.  Next the main 16-pin connector will be manually  wired into the vehicle. 
 
 
 
Pin Color Description 
1  Black  Ground; connect to good chassis ground or d irectly to battery negative () terminal 
2  Red  Ignition power; connect to a fused key on +12 V power source 
3  Black USB - Dedicated 
4  N/C  Reserved 
5  Red USB - Dedicated 
6  Green USB - Dedicated 
7  Blue  *OPTIONAL* Ground output; connect to an exte rnal auxiliary device (1.5A max current) 
8  White USB - Dedicated 
9  Green...

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7.  Install USB cable so the PC end of the cable is easily accessible and route the gauge end of cable to 
the gauge mounting location.  USB cable is meant to  be permanently installed to gauge and left in 
vehicle.  Stow PC end of cable in location such as  glove box or center console, etc. 
Wideband Failsafe Configuration 
 
In this tab, the AFR monitoring and alarm output fu nctionality of the W ideband Failsafe can be configu red.   
 
 
   
 
Air to Fuel Ratio vs. Pressure 
Description...

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Logger 
Button Description 
Log Percentage  Displays current amount of data recorded 
Download Log Downloads all the collected AFR data that is stored
 in the logger; will prompt to save log to disk; 
log files saved as .daq for direct viewing in AEMda ta program    
Clear Log   Clears all stored AFR data from the logg er   
RPM 
Parameter Description 
RPM  Displays the current engine speed dictated by t he Pulses Per Revolution option. 
Option Description 
Pulses Per  
Revolution...

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Gauge Configuration 
  
In this tab, the gauge lighting and display features can be configured. 
 
 
       
Display Option 
Option Description 
Center 
Display  Center display reading configuration; use to select
 either pressure (InHg / PSIg or Bar) or O2 sensor 
(AFR or Lambda) 
Installed 
Faceplate  Faceplate configuration; use to match 24 outer LEDs
 to faceplate with either Pressure (InHg / PSIg 
or Bar) or O2 sensor (AFR or Lambda) [See Appendix  II – Changing Faceplate / Bezel]  
Alarm...

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Wideband Failsafe Tuning 
  
The following is a basic guideline strategy for configuring the Wideband Failsafe for the first time.  The 
ideal time to configure the Wideband Failsafe is wh ile the vehicle is being dyno tuned.  Ensure your 
engine is fully functional mechanically before star ting to configure the Wideband Failsafe!    
 
1.  In the W ideband Failsafe Configuration tab, clic k Clear Graph and Reset Limits to zero all settings. 
 
2.  If a boosted pressure scale is selected, there...

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3.  Run the engine as you would normally drive the vehicle then complete a series of long sweeping high 
load 3rd and 4th gear pulls going from low to high RPM each time to  populate the graph with AFR data.  
Avoid making quick hard pulls as this may skew the  AFR data points. Repeat this procedure until a 
baseline AFR curve is established. Note: You may no tice that a few random AFR data points are 
plotted well outside of the normal AFR curve. This  is caused by dynamic tip-in wall wetting...