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Circuit Inspection

WARNING: This page is about a different car, the 2024 Kia Forte. However, it is still accessible from the selected car via links, so may be relevant.
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Module Inspection
Inspection Item Inspection Condition (+) Probe (-) Probe Specification
Connector Terminal Connector Terminal
Voltage inspection (TCM ←→ Chassis ground)
  1. Disconnect TCM connector.
  2. Ignition "ON".
TCM connector 17, 65, 66 (Memory power) Chassis ground - B+
TCM connector 3 (ON/START Input) Chassis ground - B+
Voltage inspection (PCM ←→ Chassis ground)
  1. Disconnect PCM connector.
  2. Ignition "ON".
PCM connector 64, 85 (Memory power) Chassis ground - B+
Open in circuit inspection (TCM ←→ Chassis ground)
  1. Ignition "OFF".
  2. Disconnect the TCM connector.
TCM connector 57, 58, 61 (ground) Chassis ground - Approx. below 1Ω
Open in circuit inspection (PCM ←→ Chassis ground)
  1. Ignition "OFF".
  2. Disconnect the PCM connector.
PCM connector 45, 46 (ground) Chassis ground - Approx. below 1Ω

Good 

No Good 

CAN Communication Circuit Inspection (P-CAN)
Inspection Item Inspection Condition (+) Probe (-) Probe Specification
Connector Terminal Connector Terminal
Resistance inspection (PCM, ICU)
  1. Ignition "OFF".
  2. Disconnect PCM, ICU connector.
PCM (component side) 77 (P-CAN high) PCM (component side) 60 (P-CAN low) Approx. below 120Ω
ICU (component side) 19 (P-CAN high) ICU (component side) 20 (P-CAN low) Approx. below 120Ω
Open in circuit inspection (TCM ←→ ICU)
  1. Ignition "OFF".
  2. Disconnect the TCM, ICU connector.
TCM connector 44 (P-CAN high) ICU connector 19 (P-CAN high) Approx. below 1Ω
TCM connector 45 (P-CAN low) ICU connector 20 (P-CAN low) Approx. below 1Ω
Short in circuit inspection (TCM ←→ Chassis ground)
  1. Ignition "OFF".
  2. Disconnect the TCM, ICU connector.
TCM connector 44 (P-CAN high) Chassis ground - ∞ (infinity)Ω
TCM connector 45 (P-CAN low) Chassis ground - ∞ (infinity)Ω
Short in circuit inspection (PCM ←→ Chassis ground)
  1. Ignition "OFF".
  2. Disconnect the PCM, ICU connector.
PCM connector 77 (P-CAN high) Chassis ground - ∞ (infinity)Ω
PCM connector 60 (P-CAN low) Chassis ground - ∞ (infinity)Ω
P-CAN oscilloscope (TCM)
  1. Ignition "ON".
TCM connector 44 (P-CAN high) Chassis ground - Fig.1 to 6
TCM connector 45 (P-CAN low) Chassis ground -
P-CAN oscilloscope (PCM)
  1. Ignition "ON".
PCM connector 77 (P-CAN high) Chassis ground - Fig.1 to 6
PCM connector 60 (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.
G14565592Courtesy of KIA MOTORS AMERICA, INC.
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Good 

No Good 

CAN Communication Circuit Inspection (C-CAN)
Inspection Item Inspection Condition (+) Probe (-) Probe Specification
Connector Terminal Connector Terminal
Resistance inspection (CLU, ICU)
  1. Ignition "OFF".
  2. Disconnect CLU, ICU connector.
CLU (component side) 35 (C-CAN high) CLU (component side) 34 (C-CAN low) Approx. below 120Ω
ICU (component side) 9 (C-CAN high) ICU (component side) 10 (C-CAN low) Approx. below 120Ω
Open in circuit inspection (CLU ←→ ICU)
  1. Ignition "OFF".
  2. Disconnect the CLU, ICU connector.
CLU connector 32 (C-CAN high) ICU connector 9 (C-CAN high) Approx. below 1Ω
CLU connector 33 (C-CAN low) ICU connector 10 (C-CAN low) Approx. below 1Ω
C-CAN oscilloscope (CLU)
  1. Ignition "ON".
CLU connector 32 (C-CAN high) Chassis ground - Fig.1 to 6
CLU connector 33 (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.
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Good 

No Good