Pinpoint Test

1. Ignition OFF.
2. Determine if both trailer stop/turn lamps are inoperative.

Are both trailer stop/turn lamps inoperative? 

• Yes: VERIFY the BJB fuse 63 (15A) is OK. If OK, REPAIR the trailer stop/turn lamp relay voltage supply circuit for an open. If not OK, REFER to the appropriate OEM WIRING DIAGRAMS to identify the cause for the circuit short.
• No: For an inoperative left trailer stop/turn lamp, GO to 2  .

  For an inoperative right trailer stop/turn lamp, GO to  11.

1. For the 4-pin connector, while applying the brake pedal, measure:

   Trailer Tow			Ground
   C439			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   2	CAT06 (YE)		-	Ground

2. For the 7-pin connector, while applying the brake pedal, measure:

   Trailer Tow Connector			Ground
   Trailer Tow Connector			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   1	CAT06 (YE)		-	Ground

Is the voltage greater than 11 volts? 

• Yes: The vehicle is operating correctly. SEND the trailer to an authorized camper/trailer repair facility.
• No: For the 4-pin connector, GO to  4.

  For the 7-pin connector, GO to 3  .

1. Disconnect: Trailer Tow Connector.
2. While applying the brake pedal, measure:

   Trailer Tow			Ground
   C4099			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   1	CAT06 (YE)		-	Ground

Is the voltage greater than 11 volts? 

• Yes: INSTALL a new trailer tow connector.
• No: GO to 4  .

1. Disconnect: Trailer Tow Left Stop/Turn Relay.
2. Substitute a known good relay.
3. For the 4-pin connector, while applying the brake pedal, measure:

   Trailer Tow			Ground
   C439			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   2	CAT06 (YE)		-	Ground

4. For the 7-pin connector, while applying the brake pedal, measure:

   Trailer Tow			Ground
   C4099			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   1	CAT06 (YE)		-	Ground

Is the voltage greater than 11 volts? 

• Yes: REMOVE the known good relay. INSTALL a new trailer tow turn relay.
• No: REMOVE the known good relay. GO to 5  .

1. While applying the brake pedal, measure:

   BJB			Ground
   Trailer Tow Left Stop/Turn Relay			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   2	CLS18 (GY/BN)		-	Ground

Is the voltage greater than 11 volts? 

• Yes: GO to 6  .
• No: GO to  8.

1. Measure:

   BJB			Ground
   Trailer Tow Left Stop/Turn Relay			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   3	SBB63 (WH/RD)		-	Ground

Is the voltage greater than 11 volts? 

• Yes: GO to 7  .
• No: REPAIR the circuit.

1. Measure:

   BJB			BJB
   Trailer Tow Left Stop/Turn Relay			Trailer Tow Left Stop/Turn Relay
   Pin	Circuit	Measurement / Action	Pin	Circuit
   3	SBB63 (WH/RD)		1	GD120 (BK/GN)

Is the voltage greater than 11 volts? 

• Yes: REPAIR the trailer tow left stop/turn relay output circuit to the trailer tow connector for an open.
• No: REPAIR the trailer tow left stop/turn relay ground circuit for an open.

1. Ignition ON.
2. Using a scan tool, perform the BCM on-demand self-test.
3. While applying the brake pedal, measure:

   BJB			Ground
   Trailer Tow Left Stop/Turn Relay			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   2	CLS18 (GY/BN)		-	Ground

Is the voltage greater than 11 volts? 

• Yes: INSTALL a new trailer tow turn relay.
• No: GO to  6.

1. Ignition OFF.
2. Disconnect: BCM C2280D.
3. Measure:

   BJB			Ground
   Trailer Tow Left Stop/Turn Relay			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   2	CLS18 (GY/BN)		-	Ground

Is the resistance greater than 10, 000 ohms? 

• Yes: GO to 10  .
• No: REPAIR the circuit.

1. Measure:

   BJB			BCM
   Trailer Tow Left Stop/Turn Relay			C2280D
   Pin	Circuit	Measurement / Action	Pin	Circuit
   2	CLS18 (GY/BN)		12	CLS18 (GY/YE)

Is the resistance less than 3 ohms? 

• Yes: GO to  20.
• No: REPAIR the circuit.

1. For the 4-pin connector, while applying the brake pedal, measure:

   Trailer Tow			Ground
   C439			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   1	CAT09 (GN)		-	Ground

2. For the 7-pin connector, while applying the brake pedal, measure:

   Trailer Tow			Ground
   Trailer Tow Connector			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   4	CAT09 (GN)		-	Ground

Is the voltage greater than 11 volts? 

• Yes: The vehicle is operating correctly. SEND the trailer to an authorized camper/trailer repair facility.
• No: For the 4-pin connector, GO to  13.

  For the 7-pin connector, GO to 12  .

1. Disconnect: Trailer Tow Connector.
2. While applying the brake pedal, measure:

   Trailer Tow			Ground
   C4099			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   4	CAT09 (GN)		-	Ground

Is the voltage greater than 11 volts? 

• Yes: INSTALL a new trailer tow connector.
• No: GO to 13  .

1. Disconnect: Trailer Tow Right Stop/Turn Relay.
2. Substitute a known good relay.
3. For the 4-pin connector, while applying the brake pedal, measure:

   Trailer Tow			Ground
   C439			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   1	CAT09 (GN)		-	Ground

4. For the 7-pin connector, while applying the brake pedal, measure:

   Trailer Tow			Ground
   C4099			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   4	CAT09 (GN)		-	Ground

Is the voltage greater than 11 volts? 

• Yes: REMOVE the known good relay. INSTALL a new trailer tow turn relay.
• No: REMOVE the known good relay. GO to 14  .

1. While applying the brake pedal, measure:

   BJB			Ground
   Trailer Tow Right Stop/Turn Relay			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   2	CLS19 (VT/OG)		-	Ground

Is the voltage greater than 11 volts? 

• Yes: GO to 15  .
• No: GO to  17.

1. Measure:

   BJB			Ground
   Trailer Tow Right Stop/Turn Relay			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   3	SBB63 (WH/RD)		-	Ground

Is the voltage greater than 11 volts? 

• Yes: GO to 16  .
• No: REPAIR the circuit.

1. Measure:

   BJB			BJB
   Trailer Tow Right Stop/Turn Relay			Trailer Tow Right Stop/Turn Relay
   Pin	Circuit	Measurement / Action	Pin	Circuit
   3	SBB63 (WH/RD)		1	GD120 (BK/GN)

Is the voltage greater than 11 volts? 

• Yes: REPAIR the trailer tow right stop/turn relay output circuit to the trailer tow connector for an open.
• No: REPAIR the trailer tow right stop/turn relay ground circuit for an open.

1. Ignition ON.
2. Using a scan tool, perform the BCM on-demand self-test.
3. While applying the brake pedal, measure:

   BJB			Ground
   Trailer Tow Right Stop/Turn Relay			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   2	CLS19 (VT/OG)		-	Ground

Is the voltage greater than 11 volts? 

• Yes: INSTALL a new trailer tow turn relay.
• No: GO to 18  .

1. Ignition OFF.
2. Disconnect: BCM C2280D.
3. Measure:

   BJB			Ground
   Trailer Tow Right Stop/Turn Relay			Ground
   Pin	Circuit	Measurement / Action	Pin	Circuit
   2	CLS19 (VT/OG)		-	Ground

Is the resistance greater than 10, 000 ohms? 

• Yes: GO to 19  .
• No: REPAIR the circuit.

1. Measure:

   BJB			BCM
   Trailer Tow Left Stop/Turn Relay			C2280D
   Pin	Circuit	Measurement / Action	Pin	Circuit
   2	CLS19 (VT/OG)		15	CLS19 (VT/OG)

Is the resistance less than 3 ohms? 

• Yes: GO to 20  .
• No: REPAIR the circuit.

1. Disconnect and inspect all BCM connectors.
2. Repair:
   • corrosion (install new connector or terminals - clean module pins)
   • damaged or bent pins - install new terminals/pins
   • pushed-out pins - install new pins as necessary
3. Reconnect the BCM connectors. Make sure they seat and latch correctly.
4. Operate the system and determine if the concern is still present.

Is the concern still present? 

• Yes: CHECK OASIS  for any applicable TSBs  . If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs  address this concern, INSTALL a new BCM. REFER to BODY CONTROL MODULE (BCM) - WITHOUT INTELLIGENT ACCESS (IA) , or REFER to BODY CONTROL MODULE (BCM) - WITH INTELLIGENT ACCESS (IA) .
• No: The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.