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Circuit Inspection

G14910648Courtesy of KIA MOTORS AMERICA, INC.
G14910649Courtesy of KIA MOTORS AMERICA, INC.
E-CAN Inspection
Inspection Item Inspection Condition (+) Probe (-) Probe Specification
Connector Terminal Connector Terminal
Resistance inspection (A/C control module, ICU)
  1. Ignition "OFF".
  2. Disconnect auxiliary battery (-) cable.
  3. Disconnect the connector(s) A/C control module, ICU.
 A/C control module (component side) 35 (E-CAN high) A/C control module (component side) 34 (E-CAN low) Approx. 120Ω
ICU (component side) 17 (E-CAN high) IICU (component side) 18 (E-CAN low) Approx. 120Ω
Open in circuit inspection (A/C control module ↔ ICU)
  1. Ignition "OFF".
  2. Disconnect the connector(s) A/C control module, ICU.
 A/C control module connector 35 (E-CAN high) ICU connector 17 (E-CAN high) Approx. below 1Ω
A/C control module connector 34 (E-CAN low) ICU connector 18 (E-CAN low) Approx. below 1Ω
E-CAN oscilloscope (A/C control module)
  1. Ignition "ON".
  2. Measure the waveform using VMI of KDS.
 A/C control module connector 35 (E-CAN high) Chassis ground - Fig.1 to 6
A/C control module connector 34 (E-CAN low) Chassis ground -

Information 

It is important to check CAN high and low at the same time to check the waveform of the CAN communication line. The CAN signal is in a bus idle state based on 2.5V (digital "1"), the high signal rises to 3.5V, the low signal falls to 1.5V, and the voltage difference between the high and low signals is "0" when 2V occurs. Is detected. In addition, it monitors whether the high and low signals have opposite voltages based on 2.5V like the waveform on the left, and monitors whether the current CAN signal is transmitted normally.

In CAN communication, a continuous "0" signal of 6 bits or more means occurrence of an error. 1 bit can be easily determined by obtaining the time when "SOF" (Start Of Frame), indicating the start of the frame, occurs. Check if the "0" signal of 6 bits or more occurs continuously during CAN communication waveform check.

  1. Reference voltage about 2.5V (high: 2.5V → 3.5V rise, low: 2.5V → 1.5V drop)
  2. Idle (2.5V) section of a certain period
  3. Constant data frame time
  4. High and low symmetrical frame shape
G14910650Courtesy of KIA MOTORS AMERICA, INC.
G14910651Courtesy of KIA MOTORS AMERICA, INC.
G14910652Courtesy of KIA MOTORS AMERICA, INC.
G14910653Courtesy of KIA MOTORS AMERICA, INC.
G14910654Courtesy of KIA MOTORS AMERICA, INC.
G14910655Courtesy of KIA MOTORS AMERICA, INC.

Good 

No Good 

P-CAN Inspection
Inspection Item Inspection Condition (+) Probe (-) Probe Specification
Connector Terminal Connector Terminal
Resistance inspection (VCU, ICU)
  1. Ignition "OFF".
  2. Disconnect auxiliary battery (-) cable.
  3. Disconnect the connector(s) VCU, ICU.
 VCU (component side) 77 (P-CAN high) VCU (component side) 78 (P-CAN low) Approx. 120Ω
ICU (component side) 19 (P-CAN high) ICU (component side) 20 (P-CAN low) Approx. 120Ω
Open in circuit inspection (ICU ↔ VCU)
  1. Ignition "OFF".
  2. Disconnect the connector(s) ICU, VCU.
 ICU connector 19 (P-CAN high) VCU connector 77 (P-CAN high) Approx. below 1Ω
ICU connector 20 (P-CAN low) VCU connector 78 (P-CAN low) Approx. below 1Ω
P-CAN oscilloscope (ICU)
  1. Ignition "ON".
  2. Measure the waveform using VMI of KDS.
 ICU connector 19 (P-CAN high) Chassis ground - Fig.1 to 6
ICU connector 20 (P-CAN low) Chassis ground -

Information 

It is important to check CAN high and low at the same time to check the waveform of the CAN communication line. The CAN signal is in a bus idle state based on 2.5V (digital "1"), the high signal rises to 3.5V, the low signal falls to 1.5V, and the voltage difference between the high and low signals is "0" when 2V occurs. Is detected. In addition, it monitors whether the high and low signals have opposite voltages based on 2.5V like the waveform on the left, and monitors whether the current CAN signal is transmitted normally.

In CAN communication, a continuous "0" signal of 6 bits or more means occurrence of an error. 1 bit can be easily determined by obtaining the time when "SOF" (Start Of Frame), indicating the start of the frame, occurs. Check if the "0" signal of 6 bits or more occurs continuously during CAN communication waveform check.

  1. Reference voltage about 2.5V (high: 2.5V → 3.5V rise, low: 2.5V → 1.5V drop)
  2. Idle (2.5V) section of a certain period
  3. Constant data frame time
  4. High and low symmetrical frame shape
G14910656Courtesy of KIA MOTORS AMERICA, INC.
G14910657Courtesy of KIA MOTORS AMERICA, INC.
G14910658Courtesy of KIA MOTORS AMERICA, INC.
G14910659Courtesy of KIA MOTORS AMERICA, INC.
G14910660Courtesy of KIA MOTORS AMERICA, INC.
G14910661Courtesy of KIA MOTORS AMERICA, INC.

Good 

No Good 

Module Inspection
Inspection Item Inspection Condition (+) Probe (-) Probe Specification
Connector Terminal Connector Terminal
Power inspection (A/C control module ↔ Chassis ground)
  1. Disconnect the connector(s) A/C control module.
  2. Ignition "ON".
 A/C control module connector 15, 16 (memory input) Chassis ground - B+
A/C control module connector 31 (ON/START Input) Chassis ground - B+
A/C control module connector 32 (IG3 input) Chassis ground - B+
Open in circuit inspection (A/C control module ↔ Chassis ground)
  1. Ignition "OFF".
  2. Disconnect the connector(s) A/C control module.
 A/C control module connector 16, 17, 40 (ground) Chassis ground - Approx. below 1Ω

Good 

No Good 

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