Terminals Of ECM

CHECK ECM

Fig 1: Identifying ECM Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the voltages of the wire harness side connectors.

Standard voltage:

TERMINALS VOLTAGES CHART

Symbols (Terminals No.)	Wiring Color	Terminal Description	Condition	Specified Condition
TC (A21-27) - E1 (C20-104)	P-W	DTC output signal	Ignition switch ON	10 to 14 V
TC (A21-27)-E1 (C20-104)	P-W	DTC output signal	Ignition switch ON Connect terminals TC and CG of DLC3	Below 2 V
ST1-(A21-35)-E1 (C20-104)	Y-W	Cruise cancel input signal	Ignition switch ON Depress brake pedal	Below 1 V
ST1-(A21-35)-E1 (C20-104)	Y-W	Cruise cancel input signal	Ignition switch ON Release brake pedal	10 to 14 V
STP (A21-36)-E1(C20-104)	G-W	Stop light switch input signal	Ignition switch ON Depress brake pedal	10 to 14 V
STP (A21-36)-E1 (C20-104)	G-W	Stop light switch input signal	Ignition switch ON Release brake pedal	Below 1 V
CCS(A21-40)-E1 (C20-104)	L-W	Cruise control main switch output signal	Ignition switch ON	10 to 14 V
CCS(A21-40)-E1 (C20-104)	L-W	Cruise control main switch output signal	Ignition switch ON CANCEL switch held ON	6.6 to 10.1 V
CCS (A21-40) - E1 (C20-104)	L-W	Cruise control main switch output signal	Ignition switch ON -/SET switch held ON	4.5 to 7.1V
CCS (A21-40) - E1 (C20-104)	L-W	Cruise control main switch output signal	Ignition switch ON +/RES switch held ON	2.3 to 4.5 V
CCS(A21-40)-E1 (C20-104)	L-W	Cruise control main switch output signal	Ignition switch ON MAIN switch held ON	Below 1 V
E1 (C20-104)-Body ground	W - Body ground	Ground	Always	Below 1 V
D(C20-56)-E1 (C20-104)	L-W	Clutch switch input signal	Ignition switch ON Depress clutch pedal	Below 1 V
D (C20-56)-E1 (C20-104)	L-W	Clutch switch input signal	Ignition switch ON Release clutch pedal	10 to 14 V
CANH (A21-41)-E1 (C20-104)	L-W	CAN communication line	Ignition switch ON	Pulse generation (see WAVEFORM 1 )
CANL (A21-49) - E1 (C20-104)	W-W	CAN communication line	Ignition switch ON	Pulse generation (see WAVEFORM 2 )

If the result is not as specified, there may be a malfunction on the wire harness side.

WAVEFORM 1 (Reference) CAN communication signal

WAVEFORM 1 REFERENCE CHART

ECM Terminal Names	Between CANH and E1
Tester Ranges	1 V/DIV, 10 ms/DIV
Conditions	Engine stops and ignition switch ON

HINT:

The waveform varies depending on the CAN communication signal.

Fig 2: Waveform Graph (Waveform 1)

WAVEFORM 2(Reference) CAN communication signal

WAVEFORM 2 REFERENCE CHART

ECM Terminal Names	Between CANL and E1
Tester Ranges	1 V/DIV, 10 ms/DIV
Conditions	Engine stops and ignition switch ON

HINT:

The waveform varies depending on the CAN communication signal.

Fig 3: Waveform Graph (Waveform 2)