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Update E24-SEFMJ-white-civic-si.md

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OEM-Docs/Honda/E24-SEFMJ-white-civic-si/E24-SEFMJ-white-civic-si.md
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# General Context
SEFMJ Honda protocol running 9600 K-line communication between 2004 Honda ECU and multiplex module within body control unit / cabin fuse box.
SEFMJ Honda protocol running 9600 K-line (effectively 12v serial port) communication between 2004 Honda ECU and multiplex module within body control unit (BCM) / cabin fuse box.
Some packets are sent my BCM some packets are sent by ECU. Assumption is that BCM is master thus first packet in the cycle is coming from BCM.
Some packets are sent my BCM, some packets are sent by ECU. Assumption is that BCM is master thus first packet in the cycle is coming from BCM.
![image](https://user-images.githubusercontent.com/48498823/224524802-0bbde452-66a4-43b7-95c5-b523dc23cb63.png)
@ -13,14 +13,25 @@ Byte packets are clearly CRC-terminated, for instance 0x140 is crc of 1,0,0 pack
![image](https://user-images.githubusercontent.com/48498823/224524734-9c9ed54d-0ecd-4aa1-a46e-3e1f9ce53acb.png)
# Available data
Schematics: A bunch of 2003-acura-rsx PDF files at https://github.com/rusefi/rusefi_documentation/tree/master/OEM-Docs/Honda
* Bench setup in NJ: just BCM sending out same five byte packet see https://rusefi.com/forum/viewtopic.php?p=47371#p47371
* a bunch of logic analyzer recordings of real while honda civic, see below
# Problem statement
* ECU seem to be reporting CLT temperature to BDM and eventually for dash board / instrument cluster
* ECU seem to be reporting CLT temperature to BDM and eventually for dash board / instrument cluster.
* BDM seem to be reporting state of A/C request button to ECU
* BCM seem to be reporting state of A/C request button to ECU.
Open question: which packets are sent by which of the two devices?
Open question: how is A/C request encoded? Partial answer: looks like third byte 0x80 see https://github.com/rusefi/hellen125honda-issues/issues/26#issuecomment-1464826791
Open question: how is CLT encided in what packets?
# What we have