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Circuit Inspection

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C-CAN Inspection
Inspection Item Inspection Condition (+) Probe (-) Probe Specification
Connector Terminal Connector Terminal
Resistance inspection (SRSCM, ICU)
  1. Ignition "OFF".
  2. Disconnect auxiliary battery (-) cable.
  3. Disconnect the connector(s) SRSCM, ICU.
 SRSCM (component side) 27 (C-CAN high) SRSCM (component side) 26 (C-CAN low) Approx. 120Ω
ICU (component side) 21 (C-CAN high) ICU (component side) 22 (C-CAN low) Approx. 120Ω
Open in circuit inspection (IEB ↔ ICU)
  1. Ignition "OFF".
  2. Disconnect the connector(s) IEB, ICU.
 IEB connector 27 (C-CAN high) ICU connector 21 (C-CAN high) Approx. below 1Ω
IEB connector 26 (C-CAN low) ICU connector 22 (C-CAN low) Approx. below 1Ω
C-CAN oscilloscope (IEB)
  1. Ignition "ON".
  2. Measure the waveform using VMI of KDS.
 IEB connector 27 (C-CAN high) Chassis ground - Fig.1 to 6
IEB connector 26 (C-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
G14910570Courtesy of KIA MOTORS AMERICA, INC.
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G14910574Courtesy of KIA MOTORS AMERICA, INC.
G14910575Courtesy of KIA MOTORS AMERICA, INC.

Good 

No Good 

G-CAN Inspection
Inspection Item Inspection Condition (+) Probe (-) Probe Specification
Connector Terminal Connector Terminal
Resistance inspection (BMS, ICU)
  1. Ignition "OFF".
  2. Disconnect auxiliary battery (-) cable.
  3. Disconnect the connector(s) BMS, ICU.
 BMS (component side) 20 (G-CAN high) BMS (component side) 19 (G-CAN low) Approx. 120Ω
ICU (component side) 29 (G-CAN high) IICU (component side) 30 (G-CAN low) Approx. 120Ω
Open in circuit inspection (IEB ↔ ICU)
  1. Ignition "OFF".
  2. Disconnect the connector(s) IEB, ICU.
 IEB connector 21 (G-CAN high) ICU connector 29 (G-CAN high) Approx. below 1Ω
IEB connector 22 (G-CAN low) ICU connector 30 (G-CAN low) Approx. below 1Ω
G-CAN oscilloscope (IEB)
  1. Ignition "ON".
  2. Measure the waveform using VMI of KDS.
 IEB connector 21 (G-CAN high) ICU connector - Fig.1 to 6
IEB connector 22 (G-CAN low) ICU connector -

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
G14910576Courtesy of KIA MOTORS AMERICA, INC.
G14910577Courtesy of KIA MOTORS AMERICA, INC.
G14910578Courtesy of KIA MOTORS AMERICA, INC.
G14910579Courtesy of KIA MOTORS AMERICA, INC.
G14910580Courtesy of KIA MOTORS AMERICA, INC.
G14910581Courtesy 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)
  1. Ignition "OFF".
  2. Disconnect the connector(s) VCU.
 VCU (component side) 77 (P-CAN high) VCU (component side) 78 (P-CAN low) Approx. 120Ω
Resistance inspection (ICU)
  1. Ignition "OFF".
  2. Disconnect the connector(s) ICU.
 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 and 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
G14910582Courtesy of KIA MOTORS AMERICA, INC.
G14910583Courtesy of KIA MOTORS AMERICA, INC.
G14910584Courtesy of KIA MOTORS AMERICA, INC.
G14910585Courtesy of KIA MOTORS AMERICA, INC.
G14910586Courtesy of KIA MOTORS AMERICA, INC.
G14910587Courtesy of KIA MOTORS AMERICA, INC.

Good 

No Good 

Module Inspection
Inspection Item Inspection Condition (+) Probe (-) Probe Specification
Connector Terminal Connector Terminal
Power inspection (IEB ↔ Chassis ground)
  1. Disconnect the connector(s) IEB.
  2. Ignition "ON".
 IEB connector 1, 30 (Memory power) Chassis ground - B+
IEB connector 44 (ON/START Input) Chassis ground - B+
Open in circuit inspection (IEB ↔ Chassis ground)
  1. Ignition "OFF".
  2. Disconnect the connector(s) IEB.
 IEB connector 38, 40 (ground) Chassis ground - Approx. below 1Ω

Good 

No Good 

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