Kia Niro: Hybrid Control System / Troubleshooting

Strong vibration may break sensors, actuators or relays

DO NOT sprinkle water directly into the engine compartment or electronic components.

Never pull on the wiring harness when disconnecting connectors.

When removing the connector with a latch, press or pull locking lever.

Listen for a click when locking connectors. This sound indicates that they are securely locked.

When a tester is used to check for continuity, or to measure voltage, always insert tester probe from wire harness side.

Check waterproof connector terminals from the connector side. Waterproof connectors cannot be accessed from harness side.

• Use a fine wire to prevent damage to the terminal. • Do not damage the terminal when inserting the tester lead.

While the connector is connected:

Hold the connector, check connecting condition and locking efficiency.

When the connector is disconnected:

Check missed terminal, crimped terminal or broken core wire by slightly pulling the wire harness.

Visually check for rust, contamination, deformation and bend.

Check terminal tightening condition:

Insert a spare male terminal into a female terminal, and then check terminal tightening conditions.

Pull lightly on individual wires to ensure that each wire is secured in the terminal.

Clean the contact points using air gun and/or shop rag.

Never use sand paper when polishing the contact points, otherwise the contact point may be damaged.

In case of abnormal contact pressure, replace the female terminal.

Continuity Check

Voltage Check

When measuring the resistance, lightly shake the wire harness vertically and horizontally..

Specification (Resistance)

1Ω or less → Normal Circuit

1MΩ or Higher → Open Circuit

Disconnect connectors (A) and (C), and measure the resistance between connectors (A) and (C) as shown in [FIG. 2].

In [FIG. 2], the measured resistances of lines 1 and 2 are higher than 1MΩ and below 1 Ω respectively. Specifically, an open circuit is in line 1. (Line 2 is normal.) To find the exact broken point, check sub line of line 1 as described in the next step.

Disconnect connector (B), and measure the resistances between connectors (C) and (B1) and between (B2) and (A) as shown in [FIG. 3].

In this case the measured resistance between connector (C) and (B1) is higher than 1MΩ and the open circuit is between terminal 1 of connector (C) and terminal 1 of connector (B1).

With each connector still connected, measure the voltage between the chassis ground and terminal 1 of each connectors (A), (B) and (C) as shown in [FIG. 4].

The measured voltages of each connector are 5V, 5V and 0V respectively. So the open circuit is between connectors (C) and (B).

Continuity Check with Chassis Ground

Lightly shake the wire harness above and below, or from side to side when measuring the resistance.

Specification (Resistance)

1Ω or less → Short to Ground Circuit

1MΩ or Higher → Normal Circuit

Disconnect connectors (A) and (C), and measure the resistance between connector (A) and Chassis Ground as shown in [FIG. 6].

The measured resistances of lines 1 and 2 in this example are below 1 Ω and higher than 1 MΩ respectively. Specifically, a short to ground circuit is in line 1. (Line 2 is normal.) To find the exact broken point, check the sub line of line 1 as described in the following step.

Disconnect connector (B), and measure the resistance between connector (A) and chassis ground, and between (B1) and chassis ground as shown in [FIG. 7].

The measured resistance between connector (B1) and chassis ground is 1Ω or less. The short to ground circuit is between terminal 1 of connector (C) and terminal 1 of connector (B1).