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Part 2




Horns Inoperative (Continued)

Proposal Template

4. Test for less than 2 ohm in the signal circuit end to end.

• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, replace the [CC] [control module].

• If less than [XX]

Test Example - Discrete (Switch) Signal Circuit Pulled Low In The Control Module, Using a Scan Tool
1. Ignition ON.
2. Verify the scan tool [XX] parameter is [scan tool open switch value].

• If not [XX]

1. Ignition OFF, disconnect the harness connector at the [CC] [XX] control module.
2. Test for less than 1 V between the signal circuit terminal [Y] and ground.

• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the [XX] control module.

• If [XX]

3. Install a 3 A fused jumper wire between the signal circuit terminal [Y] and the [B+, ignition, or control] circuit terminal [X].
4. Verify the scan tool [XX] parameter is [scan tool closed switch value].

• If not [XX]

1. Ignition OFF, disconnect the harness connector at the [CC] [XX] control module.
2. Test for infinite resistance between the signal circuit terminal [Y] and ground.

• If less than infinite resistance, repair the short to ground on the circuit.

• If infinite resistance

3. Test for less than 2 ohm in the signal circuit end to end.

• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, replace the [CC] [control module].

• If [XX]

Test Example - Discrete (Switch) Signal Circuit Pulled High In The Control Module, Using a Scan Tool
1. Ignition ON.
2. Verify the scan tool [XX] parameter is [scan tool open switch value].

• If not [XX]

1. Ignition OFF, disconnect the harness connector at the [CC] [XX] control module.
2. Test for infinite resistance between the signal circuit terminal [Y] and ground.

• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, replace the engine control module.

• If [XX]

3. Install a 3 A fused jumper wire between the signal circuit terminal [Y] and the [B+, ignition, or control] circuit terminal [X].
4. Verify the scan tool [XX] parameter is [scan tool closed switch value].

• If not [XX]

1. Ignition OFF, disconnect the harness connector at the [CC] [XX] control module, ignition ON.
2. Test for less than 1 V between the signal circuit terminal [Y] and ground.

• If 1 V or greater, repair the short to voltage on the circuit.

• If less than 1 V

3. Ignition OFF.
4. Test for less than 2 ohm in the signal circuit end to end.

• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, replace the [CC] [control module].

• If [XX]

Test Example - Discrete (Switch) Signal Circuit Pulled High Or Low In The Control Module, Using a DMM

Note: The signal circuit template testing uses a scan tool parameter to verify the signal circuit functions. When there is no scan tool parameter supported or an active parameter when there's an open circuit condition, use the following test in place of using the scan tool. This test does not verify the circuit between the control modules internal pull up resister and the micro-processor chip.

Signal circuit tests when there is no scan tool support.

Pulled High In The Control Module
1. Ignition ON.
2. Test for 4.8-5.2 V between the signal circuit terminal [X] and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the [CC] [XX] control module.
2. Test for infinite resistance between the signal circuit and ground.

• If less than infinite resistance, repair the short to ground on the circuit.

• If infinite resistance

3. Test for less than 2 ohm in the signal circuit end to end.

• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, replace the [CC] [control module].

• If greater than for 5.2 V

1. Ignition OFF, disconnect the harness connector at the [CC] [XX] control module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.

• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the [CC] [control module].

• If within 4.8-5.2 V

Pulled Low In The Control Module
1. Ignition OFF.
2. Test for XX-YY ohm between the signal circuit terminal [X] and ground.

• If less than XX ohm

1. Disconnect the harness connector at the [CC] [XX] control module.
2. Test for infinite resistance between the signal circuit and ground.

• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, replace the [CC] [control module].

• If greater than for YY ohm

1. Disconnect the harness connector at the [CC] [XX] control module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.

• If 1 V or greater, repair the short to voltage on the circuit.

• If less than 1 V

3. Ignition OFF.
4. Test for less than 2 ohm in the signal circuit end to end.

• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, replace the [CC] [control module].

• If within XX-YY ohm

Control (Output) Circuits

Test Example - Control Circuit Pulled Low In The Control Module
1. Connect a test lamp between the control circuit terminal [X] and the [B+, ignition, or control] circuit terminal [X].
2. Verify the test lamp turns ON and OFF when Commanding the [XX component/function] ON and OFF with a scan tool.

• If the test lamp is always ON

1. Ignition OFF, disconnect the harness connector at the [CC] [XX] control module.
2. Test for infinite resistance between the control circuit and ground.

• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, replace the [CC] [control module].

• If the test lamp is always OFF

1. Ignition OFF, disconnect the harness connector at the [CC] [XX] control module, ignition ON.
2. Test for less than 1 V between the control circuit and ground.

• If 1 V or greater, repair the short to voltage on the circuit.

• If less than 1 V

3. Ignition OFF.
4. Test for less than 2 ohm in the control circuit end to end.

• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, replace the [CC] [control module].

• If the test lamp turns ON and OFF

Test Example - Control Circuit Pulled High In The Control Module
1. Connect a test lamp between the control circuit terminal [X] and the [B+, ignition, or control] circuit terminal [X].
2. Verify the test lamp turns ON and OFF when Commanding the [XX component/function] ON and OFF with a scan tool.

• If the test lamp is always ON

1. Ignition OFF, disconnect the harness connector at the [CC] [XX] control module, ignition ON.
2. Test for less than 1 V between the control circuit and ground.

• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the [CC] [control module].

• If the test lamp is always OFF

1. Ignition OFF, disconnect the harness connector at the [CC] [XX] control module.
2. Test for infinite resistance between the control circuit and ground.

• If less than infinite resistance, repair the short to ground on the circuit.

• If infinite resistance

3. Test for less than 2 ohm in the control circuit end to end.

• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, replace the [CC] [control module].

• If the test lamp turns ON and OFF

Test Example - Dual Control Circuits (Switches Between Low And High Voltage)

Note: These circuits are normally grounded and individually pulled high in the module. Each circuit is tested first as a low reference circuit (see template).

1. Connect a test lamp between the control circuit terminal [X] and the control circuit terminal [Y].
2. Verify the test lamp turns ON when commanding the [LOCK/UP] and [UNLOCK/DOWN] states with a scan tool.

• If the test lamp remains OFF during either of the commands

1. Ignition OFF, disconnect the harness connector at the [CC] [XX] control module.
2. Test for infinite resistance between each control circuit and ground.

• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, replace the [CC] [control module].

• If the test lamp turns ON for each command

Example 3 - Dual Control Circuits (AC Riding On a DC Voltage) Intended For Speaker Circuits

Note: These circuits normally have a quiescent output voltage 1/2 the DC supply voltage. Each control circuit is first tested as a voltage reference circuit then tested for an AC output voltage between the 2 control circuits.

1. Ignition ON, test for 5-7 V between the control circuit terminal [1] and ground.

• If less than 5 V

1. Ignition OFF, disconnect the harness connector at the [CC] [XX] control module.
2. Test for infinite resistance between the control circuit and ground.

• If less than infinite resistance, repair the short to ground on the circuit.

• If infinite resistance

3. Test for less than 2 ohm in the control circuit end to end.

• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, replace the [CC] [control module].

• If greater than 7 V

1. Ignition OFF, disconnect the harness connector at the [CC] [XX] control module, ignition ON.
2. Test for less than 1 V between the control circuit and ground.

• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the [CC] [control module].

• If within 5-7 V

2. Test for greater than 1 V AC between the control circuit terminal [1] and the control circuit terminal [2].

• If 1 V AC or less
Replace the [CC] [control module].

• If greater than 1 V AC

Note: The control circuit template testing uses a scan tool to perform the control circuit functions. When there is no scan tool output control supported use the following test in place of the scan tool.

Control Circuit Tests When There Is No Scan Tool Support

Turn the [XX component/function] ON and OFF with the [XX component/switch].

Verify the test lamp turns ON and OFF when changing between the selected states.

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