Monday, March 21, 2016

CTSHO005.2 Honda Steering Wheel Stalk Control Adaptor

This is another adapter example that you may need to connect aftermarket audio to wheel buttons and some more signals (dash light, reverse, parking brake, etc).

Link to - 39 GBP + 12 GBP (delivery).

This is a patch lead, PDF is here.

In default configuration it works as follows: it outputs resistance change depends on button pressed.
These are readings on KEY1 wire
Idle (nothing pressed)11.5 MOhm
189 kOhm (after 1st time pressed)
Volume Down22.00 kOhm
Volume Up16.43 kOhm
Seek Backward11.82 kOhm
Seek Forward8.58 kOhm
Middle (circle button)2.07 kOhm

I believe, you can change to voltage too just follow the instructions.

This is an adapter doc, PDF is here.

Wiring for Civic connectors.
Note that ACC signal is taken from 2nd connector both with CAN bus.

Let's open this sucker.

Main ICs are:
NXP TJA1040 - High speed CAN transceiver
Renesas Eelectronics R5F2123 - R8C Series 16 bit 3 kB RAM 64 kB Flash Microcontroller SMT
Fairchild FDS4953 - Dual 30V P-Channel PowerTrench MOSFET

Little man says hi!

Standby consumption.
When you first plug it, it will drain about 25-30mA for a few seconds and than falls into 3mA even when you send 12V to ACC.

The only addition I've made is adding original Honda's AUX 3 wires (on right) to it.

42,100 km | 2Y 9M

Wednesday, March 16, 2016

Honda Steering Wheel Stalk Control Adaptor from Teder

This is an adapter from my Civic they local dealers put for aftermarket multimedia units like my prev Blaupunkt New York 830 works with buttons on steering wheel.

Why you need that?
Because on modern cars, all communication done via CAN bus. Same on most late Hondas. All buttons signals going into CAN and most of aftermarket units (Pioneer, Alpine, Clarion, etc) not have CAN module to decode that signals. So you need an adapter.

How it works?
This one works with voltage change. Other units works with resistance change.

These are readings on ORANGE wire that my adapter outputs
Idle (nothing pressed)4.933 V
Volume Down3.946 V
Volume Up3.353 V
Seek Forward2.735 V
Seek Backward2.145 V
Middle (circle button)1.575 V

Label on the unit says:
Teder Audio
Honda Civic
Hardware version 1.00
Software version 1.07
Date 2013-06-04. I got my car 2013-07-04 - close enough.

Let's crack this sucker open!

Main ICs are:

CPU: STI STM32F103C8 - Mainstream Performance line, ARM Cortex-M3 MCU with 64 Kbytes Flash, 72 MHz CPU, motor control, USB and CAN.

CAN: Microchip MCP2551 - MCP2551 is a high-speed CAN transceiver.

Looks like this unit is made here in Israel by

Below are Honda's main connectors.
Big one with power supply and speakers output.

Smaller one that has CAN bus, AUX in and ACC.

Browns are CAN, violet are AUX L+R in with green (GROUND for them).

42,100 km | 2Y 9M