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--- techtalk:evo:elec04 [2021/08/18 19:48]
ixl2relax [SDB - Serial Data Bus]
+++ techtalk:evo:elec04 [2024/05/14 00:14] (current)
ixl2relax [SDB - Serial Data Bus]
@@ Line 7: / Line 7: @@
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-====== SDB - Serial Data Bus ======
+====== SDB - Serial Data Bus (2004-2013) ======
-In 2004, HD implemented the serial data bus (SDB) on all Sportster models. This single wire, digital communications link, provides a means for the Ignition Control Module (ICM), the Turn Signal Module (TSM/TSSM) and Speedometer/Tachometer to intelligently communicate with one another. There is a 4-pin 'port' connector (called a serial data link) to allow external computer connection to the SDB. It is located near the MaxiFuse.
+For 2004-2013, HD implemented the serial data bus (SDB) on all Sportster models. This single wire, digital communications link, provides a means for the Ignition Control Module (ICM-2004-2006) or Engine Control Module (ECM-2007-2013), the Turn Signal Module (TSM/TSSM) and Speedometer/Tachometer to intelligently communicate with one another. There is a 4-pin 'port' connector (called a serial data link) to allow external computer connection to the SDB. It is located near the MaxiFuse.
-The SDB link allowed the ICM to be reprogrammable because it allowed the factory and the dealer the ability to use one ICM and program it for either 883 engines or 1200 engines. There are updates that can be dealer 'flashed' into the ICM when new parameters will resolve known problems.
+The SDB link allows the ICM/ECM to be reprogrammable - That allows the factory and dealer to use a stock-version module and program it for use on either the 883 engines or 1200 engines. There are updates that can be dealer 'flashed' into the module when new parameters will resolve known problems.
-The ICM, TSM & Speedo/Tach regularly communicate their current status to one another. When all operating parameters on the serial data line are within specifications, a state of health message is sent between the components.
+The ICM/ECM, TSM & Speedo/Tach regularly communicate their current status to one another. When all operating parameters on the serial data line are within specifications, a state of health message is sent between the components.
-The SDB is designed upon a standard SAE serial communication protocol callded "J1850". The digital data is transmitted and received on a single wire at around 10.4 Kbps. This protocol was used thru the 2013 model year.
+A DTC of U1016 (Diagnostic Code) is set when the ICM can't send that 'state of health message'.\\
+--- That code is also set if there was communications, but it stopped at some point.\\
+A DTC of U1097 is set by the Speedo if it can't send the 'state of health message'.
+--- That code is also set if there was communications, but it stopped at some point.\\
+A DTC of U1255 is set when no messages are communicated at power up.\\
+The SDB is designed upon a standard SAE serial communication protocol called "J1850". The digital data is transmitted and received on a single wire at around 10.4 Kbps. This protocol was used thru the 2013 model year.
 Diagnostic Troubleshooting Codes (DTC) are available to be read on the speedometer. A DTC of U1016 indicates that the ECM is not capable of sending this state of health message. A DTC of U1255 indicates that no messages were present during power up of the current key cycle. A DTC of U1016 indicates that there was communication on the data bus since power up, but communication was lost or interrupted during that key cycle.