WS5 - Scan tool Diagnostics

Scan Tool Diagnostics
Toyota 1ZZ engine.

1. Scan Tool Data
Connect the scanner, power it on, follow the instructions and input the correct vehicle information it asks for so you can view data.

Type of information	Letter to describe it	Value of data	Units of data
Engine Load(how much air comes in)	AFM(MAF)	2.58	gm/s
Engine RPM	Engine Speed	701	RPM
Throttle Angle	Throttle position	11	%
Engine coolant temperature	Coolant Temperature	74	degree
Intake air temperature	Intake air temperature	22	degree
Fuel injection open pulse	Injector pulse width	2.7	ms
Transmission select position	Shift	4th
Vehicle Speed	Vehicle Speed	0	km/h
Oxygen Sensor	O2 sensor B1 S1	0.890	v
Fuel Trim	Short fuel trim #1	-20.3	%
Idle Control	IAC duty ratio	37.5	%
Power Steering condition	PS signal	OFF
Air conditioning condition	A/C cut signal	ON
Exhaust gas recirculation(EGR)
Fuel EVAP or Purge condition	EVAP VSV	OFF
Malfunction indicator light(MIL)	MIL / Warning light	OFF
Barometric Pressure

2. Trouble code or fault codes

3. Lecture put in fault
Find your lecture and have him create a fault under the hood

4. Record New Codes

The new DTC is P0120 Throttle position sensor circuit malfunction.

5. Find what data has changed

Letter to describe it	Value of data	Units for data
Throttle Position	0	%

6. Visual inspection to find fault

No fault found by visual inspection.

7. Repair fault
check the voltage

Voltage of ground

reference voltage

signal voltage

Reference voltage = 16.8mv  Signal voltage = 2.2mv   Ground = 0.3mv
The reference voltage should be 5V, the wire of reference between TPS and ECU shorted to ground.
Then let the lecturer fix it.

Clear the codes and recheck the codes

Clear the codes

clear the codes

Recheck the codes

The scan tool can read the live data from the ECU, it can help us to diagnosis the vehicle performance. Every sensor related to each other, by reading the data of the sensors, we can zone in the fault in which system then test circuit by multimeter or oscilloscope. So, we should built up the whole network of the vehicle electronic system in our mind and make the diagnosis easier, faster and more accurate.