Pinpoint Tests

WARNING: This page is about a different car, the 2006 Land Rover Range Rover Sport. However, it is still accessible from the selected car via links, so may be relevant.

PINPOINT TEST A : STOPLAMP SWITCH CIRCUIT FAULT (DTC C1A96-13)

TEST CONDITIONS	DETAILS/RESULTS/ACTIONS
A1: FUSE CHECK
NOTE: These tests are to be carried out if DTC C1A96-13 has been stored. This DTC indicates a fault in the Stoplamp Switch circuit between the Anti-lock Brake System Module (Pin C0506R-30) and the Stoplamp ground connection.
NOTE: The Stoplamp Switch Circuit is monitored by the Anti-lock Brake System Module on (C0506R-30) for open circuit. A small voltage is applied to the Stoplamp Switch circuit by the Anti-lock Brake System Module, this voltage grounds through the Stoplamps, the Anti-lock Brake System Module monitors this voltage for open circuit.
NOTE: The Stoplamp Switch and Brake Switch are fused separately.
	1. Set the Ignition State to the on position and operate the Footbrake.
	Do all the Stoplamps illuminate correctly when the Footbrake is pressed? Yes Refer to electrical circuit diagrams and check for an open circuit fault in the Stoplamp circuit connectors, splices and wiring between the Anti-lock Brake System Module (C0506R-30) and splice joint (SJ1814). Repair the circuit as required using the approved process. Clear the stored DTC, operate the Footbrake and check for correct Stoplamp operation. No Refer to electrical circuit diagrams and check for an open circuit fault in the Stoplamp circuit connectors, splices and wiring between the Anti-lock Brake System Module (C0506R-30) and the Stoplamp Ground Circuit Eyelets (C2922-1 and C1355-1). Repair the circuit as required using the approved process. Clear the stored DTC, operate the Footbrake and check for correct Stoplamp operation.

PINPOINT TEST B : STOPLAMP SWITCH PLAUSIBILITY FAULT (DTC C1A96-24)

TEST CONDITIONS	DETAILS/RESULTS/ACTIONS
B1: CUSTOMER INDUCED DTC
NOTE: These tests are to be carried out if DTC C1A96-24 has been stored. This DTC indicates plausibility - The Stoplamp Switch signal is high (Footbrake pedal pressed condition) while the vehicle is not braking.
NOTE: Plausibility detail - A DTC will be stored if the Stoplamp Switch signal is high for more than 60 seconds while the accelerator pedal is pressed and the vehicle speed is greater than 7 mph/10.8 km/h and the Anti-lock Brake System Module is not actively controlling pressure.
	1. Confirm that the fault is not being provoked by a customer driving habit (Resting a foot on the brake pedal while accelerating / cruising).
	Is the fault being provoked by a customer driving habit? Yes Advise the customer that the cause of the DTC being stored maybe due to His/Her foot resting on the Brake Pedal whilst the vehicle is in motion. Clear the stored DTC, operate the Footbrake and check for correct Stoplamp operation. No GO to B2.
B2: STOPLAMP SWITCH ADJUSTMENT CHECK
NOTE: These tests are to be carried out if DTC C1A96-24 has been stored. This DTC indicates plausibility - The Stoplamp Switch signal is high (Footbrake pedal pressed condition) while the vehicle is not braking.
	1. Check that the Stoplamp Switch is securely installed and correctly adjusted. REFER to: Stoplamp Switch (417-01 Exterior Lighting, Removal and Installation).
	Is the Stoplamp Switch securely installed and correctly adjusted? Yes GO to B3. No Refer to electrical circuit diagrams to locate the fault. Repair the circuit as required using the approved process. Clear the stored DTC, operate the Footbrake and check for correct Stoplamp operation.
B3: STOPLAMP CIRCUIT SHORT TO POWER
NOTE: If a circuit short to power is present the Stoplamps may be illuminated (Footbrake Pedal released).
	1. Using the manufacturer approved diagnostic system, monitor the Data Logger Signal, PID-2B00 Brake Input Switch Status - Brake Pedal Switch (brake lamp switch), set the Ignition State to the on position and with the Footbrake released PID-2B00 Brake Input Switch Status should show Inactive (BLS = 0).
	Does PID-2B00 Brake Input Switch Status show Inactive (BLS =0)? Yes GO to B4. No Refer to electrical circuit diagrams to locate the fault. Repair the circuit as required using the approved process. Clear the stored DTC, operate the Footbrake and check for correct Stoplamp operation.
B4: SHORT CIRCUIT TO ANOTHER POWER CIRCUIT
NOTE: A short circuit to another circuit will cause the DTC to log in the Anti-lock Brake System Module.
	1. Using the manufacturer approved diagnostic system, monitor the Data Logger Signal, PID-2B00 Brake Input Switch Status - Brake Pedal Switch (brake lamp switch), set the Ignition State to the on position and with the Footbrake released PID-2B00 Brake Input Switch Status should show Inactive (BLS = 0).
	2. Operate any electrical circuits that could supply a voltage to the Stoplamp Switch circuit.
	Does PID-2B00 Brake Input Switch Status show Inactive (BLS =0)? Yes Suspect an intermittent fault. Carry out visual and mechanical check of splice joints, all connectors and cables, check for corrosion, bent or damaged contact faces of pins, terminals and for security of connectors. Where possible flex cables while using the manufacturer approved diagnostic system to monitor the Data Logger Signal, PID-2B00 Brake Input Switch Status - Brake Pedal Switch (brake lamp switch). This test should be carried out with the ignition on and the Footbrake Pedal in the released position. BLS should remain Inactive (BLS=0). No Refer to electrical circuit diagrams to locate the fault. Repair the circuit as required using the approved process. Clear the stored DTC, operate the Footbrake and check for correct Stoplamp operation.

PINPOINT TEST C : SIGNAL COMPARE PLAUSIBILITY (DTC C1A96-62)

TEST CONDITIONS	DETAILS/RESULTS/ACTIONS
C1: STOPLAMP SWITCH CIRCUIT
NOTE: These tests are to be carried out if DTC C1A96-62 Signal Compare - Plausibility, has been stored. This DTC indicates that the Brake Lamp Switch and Brake Switch have shared the same state (both switches in the open circuit condition at the same time).
NOTE: The Stoplamp Switch contains the Brake Lamp Switch (BLS) and the Brake Switch (BS) these are located within the same housing.
NOTE: Signal Compare - Plausibility: Brake Lamp Switch and Brake Switch must not be open circuit at the same time.
NOTE: The Datalogger Signals represent the position of the Stoplamp Switch. Both Brake Lamp Switch (BLS) and the Brake Switch (BS) are shown as Active with the Footbrake pressed and Inactive with the Footbrake released . This does not directly reflect the state of the Stoplamp Switch internal switch contacts as shown in the circuit diagrams.
	1. Using the manufacturer approved diagnostic system, monitor the Data Logger Signal, PID-2B00 Brake Input Switch Status - Brake Pedal Switch (brake lamp switch) and PID-2B00 Brake Input Switch Status - Brake Pedal Switch (brake switch) inputs while the Footbrake pedal is slowly pressed & released.
	2. BLS = Brake Pedal Switch (brake lamp switch), BS = Brake Pedal Switch (brake switch). The correct inputs should be, Pedal Released BLS = Inactive (BLS = 0), BS = Inactive (BS = 0). Brief Transition (as the pedal is pressed BLS = Active (BLS = 1), BS = Inactive (BS = 0). Pedal Pressed BLS = Active (BLS = 1), BS = Active (BS = 1). If either input remains inactive during the test procedure a fault is evident.
	Did the inputs show correctly? Yes Suspect an intermittent fault. Carry out visual and mechanical check of splice joints, all connectors and cables, check for corrosion, bent or damaged contact faces of pins, terminals and for security of connectors. Where possible flex cables while using the manufacturer approved diagnostic system, monitor the Data Logger Signal, PID-2B00 Brake Input Switch Status - Brake Pedal Switch (brake lamp switch) and PID-2B00 Brake Input Switch Status - Brake Pedal Switch (brake switch). This test should be carried out with the Stoplamp Switch in both the pressed and released position independently. Refer to electrical circuit diagrams to locate the intermittent open circuit. Repair the circuit as required using the approved process. Clear the stored DTC, operate the Footbrake and check for correct Stoplamp operation. No GO to C2.
C2: STOPLAMP SWITCH CIRCUIT 2
	1. If BLS = Inactive (0) BS = Active (1) occurred with the Footbrake Released the fault is with the (BS) = Brake Pedal Switch (brake switch) circuit. If BLS = Inactive (0) BS = Active (1) occurred with the Footbrake Pressed the fault is with the (BLS) = Brake Pedal Switch (brake lamp switch) circuit.
	Did BLS (brake lamp switch) = Inactive (0) BS (brake switch) = Active (1) occur with the Footbrake Released? Yes Suspect a Stoplamp Switch (brake switch) circuit fault. Refer to electrical circuit diagrams and replace blown fuse or locate the open circuit. Repair the circuit as required using the approved process. Clear the stored DTC, operate the Footbrake and check for correct Stoplamp operation. No Suspect a Stoplamp Switch (brake lamp switch) circuit fault. Refer to electrical circuit diagrams and replace blown fuse or locate the open circuit. Repair the circuit as required using the approved process. Clear the stored DTC, operate the Footbrake and check for correct Stoplamp operation.

PINPOINT TEST D : PLAUSIBILITY - STOPLAMP SWITCH (BLS) VERSES BRAKE PRESSURE (PS) (DTC C1A96-64)

TEST CONDITIONS	DETAILS/RESULTS/ACTIONS
D1: IDS MONITOR
NOTE: These tests are to be carried out if DTC C1A96-64 Plausibility - Stoplamp Switch (BLS) verses Brake Fluid Hydraulic Pressure (PS) has been stored.
NOTE: This DTC indicates Plausibility - The Stoplamp Switch must be seen to operate before Brake Fluid Hydraulic Pressure (PS) exceeds a pressure threshold of 10 Bar.
NOTE: The Stoplamp Switch status is monitored by the Anti-lock Brake System Module (C0506R terminal 30).
NOTE: The Anti-lock Brake System Module contains an Internal Pressure Sensor and monitors the Brake Fluid Hydraulic Pressure (PS).
	1. Using the manufacturer approved diagnostic system, check for Anti-lock Brake System Module Pressure Sensor DTCs C1A99-01, C1A99-29, C1A99-49 or C1A99-64. If any of these DTCs has been stored carry out the specified action prior to investigating DTC C1A96-64.
	2. Using the manufacturer approved diagnostic system, monitor the Data Logger Signal PID-2B00 Brake Input Switch Status - Brake Pedal Switch (brake lamp switch) and PID-2B0D Brake Fluid Hydraulic Pressure (PS). When the brake pedal is pressed, the Brake Pedal Switch (brake lamp switch) status should change from Inactive (BLS = 0) to Active (BLS = 1) before the Brake Fluid Hydraulic Pressure reaches 1000KPa (10 Bar).
	Does the Brake Pedal Switch (brake lamp switch) change from Inactive (BLS = 0) to Active (BLS = 1) before the Brake Fluid Hydraulic Pressure reaches 1000KPa (10 Bar) ? Yes Suspect an intermittent Brake Lamp Switch circuit fault. Refer to electrical circuit diagrams, carry out visual and mechanical check of the of splice joints, connectors and cables of the Stoplamp Switch circuit, check for corrosion, bent or damaged contact faces of pins, terminals and for security of connectors. Where possible flex cables to attempt to induce the intermittent open circuit. Repair the circuit as required using the approved process. Clear the stored DTC, operate the Footbrake and check for correct Stoplamp operation. No GO to D2.
D2: STOPLAMP SWITCH ADJUSTMENT CHECK
NOTE: Removal and correct installation of the Stoplamp Switch will reset the adjustment. Ensure the Footbrake Pedal is fully raised against its Upstop, (pedal rest position) when installing the Stoplamp Switch.
	1. Check that the Stoplamp Switch is securely installed and correctly adjusted. REFER to: Stoplamp Switch (417-01 Exterior Lighting, Removal and Installation).
	Is the fault still present with the Stoplamp Switch securely installed and correctly adjusted? Yes Suspect a Brake Lamp Switch circuit fault. Refer to electrical circuit diagrams, carry out visual and mechanical check of the splice joints, connectors and cables of the Stoplamp Switch circuit, check for corrosion, bent or damaged contact faces of pins, terminals and for security of connectors. Repair the circuit as required using the approved process. Clear the stored DTC, operate the Footbrake and check for correct Stoplamp operation. No Adjust the Stoplamp Switch using the approved process. Clear the stored DTC, operate the Footbrake and check for correct Stoplamp operation.