Pinpoint Test D: DTC C1105:11, C1105:12 Or C1105:19
Speed Control
Pinpoint Tests
Pinpoint Test D: DTC C1105:11, C1105:12 or C1105:19
Refer to Wiring Diagram Set 31, Speed Control for schematic and connector information. Diagrams By Number
NOTE: The speed control sensor is also known as the forward looking sensor.
Normal Operation
The adaptive cruise control system is enabled when the vehicle speed is set and the speed control sensor, which is a radar unit, determines the distance and relative speed of the vehicle that is in the path of travel. The Cruise-Control Module (C-CM) commands the ABS module over the High Speed Controller Area Network (HS-CAN), which controls the vehicle brakes, to automatically apply the brakes to slow the vehicle to maintain a safe distance to the vehicle in front. The brake lamp control circuit CLS44 (VT/BN) is pulled low by the C-CM which controls the brake lamp relay. This activates the brake lamps when the brakes are applied for the adaptive cruise control system.
- DTC C1105:11 (Brake Lamp Control Circuit Short To Ground) - sets when the C-CM detects a short to ground on the brake lamp control circuit.
- DTC C1105:12 (Brake Lamp Control Circuit Short To Battery) - sets when the C-CM detects a short to battery voltage on the brake lamp control circuit.
- DTC C1105:19 (Brake Lamp Control Circuit Current Above Threshold) - sets when the C-CM detects brake lamp control circuit is above current threshold.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Brake lamp relay
- C-CM
PINPOINT TEST D: DTC C1105:11, C1105:12 OR C1105:19
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
-------------------------------------------------
D1 CHECK THE STOPLAMPS
- Verify the stoplamps operate correctly.
- Are the stoplamps continuously on?
Yes
Brake Lamp. Testing and Inspection
No
GO to D2.
-------------------------------------------------
D2 CHECK THE DTCs FROM BOTH THE CONTINUOUS AND ON-DEMAND C-CM SELF-TESTS
- Check the C-CM DTCs from the continuous and on-demand self-tests.
- Is DTC C1105:12 or DTC C1105:19 recorded?
Yes
GO to D6.
No
GO to D3.
-------------------------------------------------
D3 CHECK THE ADAPTIVE CRUISE (STOPLAMPS) RELAY
- Disconnect: Adaptive Cruise (Stoplamps) Relay.
- Carry out the adaptive cruise (stoplamps) relay component test.
- Is the adaptive cruise (stoplamps) relay OK?
Yes
GO to D4.
No
INSTALL a new adaptive cruise (stoplamps) relay. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
-------------------------------------------------
D4 CHECK CIRCUIT CBP34 (VT/BN) FOR AN OPEN
- Ignition ON.
- Measure the voltage at the adaptive cruise (stoplamps) relay, pin 85 Battery Junction Box (BJB), face side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to D5.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
-------------------------------------------------
D5 CHECK CIRCUIT CLS44 (VT/BN) CIRCUIT FOR AN OPEN
- Ignition OFF.
- Connect: Adaptive Cruise (Stoplamps) Relay.
- Disconnect: C-CM C3173.
- Ignition ON.
- Measure the voltage between the C-CM C3173-7, circuit CLS44 (VT/BN), harness side and ground.
- Is any voltage present?
Yes
GO to D8.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
-------------------------------------------------
D6 CHECK THE BRAKE LAMP CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: C-CM C3173.
- Disconnect: Adaptive Cruise (Stoplamps) Relay.
- Ignition ON.
- Measure the voltage between the C-CM C3173-7, circuit CLS44 (VT/BN), harness side and ground.
- Is any voltage present?
Yes
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
No
GO to D7.
-------------------------------------------------
D7 CHECK FOR CORRECT OPERATION WITH A KNOWN GOOD ADAPTIVE CRUISE (STOPLAMPS) RELAY INSTALLED
- Install a known good adaptive cruise (stoplamps) relay.
- Connect: C-CM C3173.
- Carry out the C-CM self-test.
- Is DTC C1105:12 or DTC C1105:19 still present?
Yes
INSTALL the original adaptive cruise (stoplamps) relay. GO to D8.
No
INSTALL a new adaptive cruise (stoplamps) relay. TEST the system for normal operation.
-------------------------------------------------
D8 CHECK FOR CORRECT C-CM OPERATION
- Disconnect the C-CM connector.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect the C-CM connector and make sure it seats correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new C-CM. REFER to Cruise-Control Module (C-CM) Service and Repair. TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. REPEAT the self-test.
-------------------------------------------------