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Engine Controls - Pin Voltage Charts: Introduction

Pin voltage charts are supplied to reduce diagnostic time. Checking pin voltages at the Electronic Control Module (ECM) determines whether it is receiving and transmitting proper voltage signals. Charts may also help determine if ECM harness is shorted or opened.

NOTE: Unless stated otherwise in testing procedures, perform all voltage tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance. Voltage readings may vary slightly due to battery condition or charging rate.
ECM VOLTAGE SPECIFICATIONS

Measure Between ECM Terminals (1) Conditions Volts
E7-14 & E8-16 Always 9-14
E7-23 & E9-16 Ignition On 9-14
E9-1 & E9-22 Ignition On 5-6
E9-7 & E9-22 Ign. On & Throttle Fully Open 3.2-4.9
E9-7 & E9-22 Ign. On & Throttle Closed 0.3-0.8
E9-8 & E8-7 Ignition On 1.1-1.5
E9-21 & E9-22 Engine Idling & Intake Air Temperature 68°F (20°C) 0.5-3.4
E9-20 & E9-22 Engine Idling & Coolant Temperature 176°F (80°C) 0.2-1.0
E10-13 & E8-16 Engine Cranking 6 Or More
E10-10 & E10-34 Engine Idling Pulse Gen.
E10-9 & E10-34 Engine Idling Pulse Gen.
E10-8 & E10-34 Engine Idling Pulse Gen.
E10-7 & E10-34 Engine Idling Pulse Gen.
E10-6 & E10-34 Engine Idling Pulse Gen.
E10-5 & E10-34 Engine Idling Pulse Gen.
E10-10 & E10-34 Ignition On 9-14
E10-9 & E10-34 Ignition On 9-14
E10-8 & E10-34 Ignition On 9-14
E10-7 & E10-34 Ignition On 9-14
E10-6 & E10-34 Ignition On 9-14
E10-5 & E10-34 Ignition On 9-14
E10-24 & E8-16 Engine Idling Pulse Gen.
E10-16 & E8-16 Engine Idling Pulse Gen.
E10-15 & E8-16 Engine Idling Pulse Gen.
E10-12 & E8-16 Engine Idling Pulse Gen.
E10-12 & E8-16 Ignition On 4.5-5.5
E8-14 & E9-22 Ignition On 4.5-5.5
E9-17 & E9-6 Engine Idling Pulse Gen.
E9-5 & E9-6 Engine Idling Pulse Gen.
E7-3 & E8-16 Taillight Switch On 7.5-14
E7-3 & E8-16 Taillight Switch Off 0-1.5
E7-2 & E8-16 Defogger Switch On 7.5-14.0
E7-2 & E8-16 Defogger Switch Off 0-1.5
E8-12 & E10-34 Ignition On 9-14
E8-6 & E10-34 Ignition On 9-14
E9-18 & E8-16 Ignition On 9-14
E9-18 & E8-16 Engine Idling 0-3
E8-2 & E10-34 Ignition On 9-14
E10-22 & E10-34 Ignition On Disconnect ECM E10 Connector 9-14
E10-23 & E10-16 Ignition On Disconnect ECM E10 Connector 9-14
E9-13 & E8-16 Maintain 2500 RPM 2 MinutesWith Engine Warm, Then Idle Pulse Gen.
E9-19 & E8-16 Maintain 2500 RPM 2 MinutesWith Engine Warm, Then Idle Pulse Gen.
E7-18 & E8-16 Maintain 2500 RPM 2 MinutesWith Engine Warm, Then Idle Pulse Gen.
E8-10 & E10-28 Idling 3 Or Less
E8-10 & E10-28 Ignition On 9-14
E8-11 & E10-28 Idling 3 Or Less
E8-11 & E10-28 Ignition On 9-14
E7-17 & E10-28 Idling 3 Or Less
E7-17 & E10-28 Ignition On 9-14
E9-15 & E8-16 Idling Pulse Gen.
E9-14 & E8-16 Idling Pulse Gen.
E10-14 & E8-16 Ignition On & Gearshift Not In "P" Or "N" 9-14
E10-14 & E8-16 Ignition On & Gearshift In "P" Or "N" 3 Or Less
E7-12 & E8-16 Ignition On & Rotate Driving Wheel Pulse Gen.
E8-5 & E8-16 Ignition On 9-14
E8-3 & E8-16 Ignition On 3 Or Less
E10-31 & E8-16 Ignition On 9-14
E7-5 & E8-16 A/C Off 2 Or Less
E7-5 & E8-16 Engine Idling & A/C Off 9-14
E7-16 & E8-16 Engine Idling & A/C On 2 Or Less
E7-16 & E8-16 Engine Idling & A/C Off 9-14
E9-2 & E9-16 Ignition On 9-14
E9-8 & E9-16 Ignition On 3-4
E8-9 & E8-16 Cooling Fan On High 9-14
E8-9 & E8-16 Cooling Fan On Low Or Off 0-2
E7-13 & E8-16 Engine Idling Pulse Gen.
E8-8 & E8-16 Ignition On & Vacuum Hose To Vapor Pressure Sensor Disconnected 9-14
E8-13 & E8-16 Ign. On & 0.6 in. Hg (2 kPa) Applied To Vapor Pressure Sensor 1.3-2.1
E7-8 & E8-16 (2) During Transmission Pulse Gen.
E7-24 & E8-16 Ign. On & Brake Pedal Pressed 7.5-14.0
E7-24 & E8-16 Ign. On & Brake Pedal Released 0-1.5
E8-15 & E8-16 Ignition On 0.4-1.6
E8-15 & E8-16 Ign. On & 5.1 in. Hg (17 kPa) Applied To EGR Valve 3.2-5.1
(1) See Fig 1.
(2) Communication bus (+) circuit between Data Link Connector (DLC) No. 3 and ECM.
Fig 1: Identifying ECM Terminals
G97A06163Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002