Pinpoint Test BB: DTC B272E
Seats
Pinpoint Tests
Pinpoint Test BB: DTC B272E
NOTE: This DTC sets for an open or short to voltage. See DTC setting description below.
Refer to Wiring Diagram Set 119, Climate Controlled Seats for schematic and connector information. Diagrams By Number
Normal Operation
The Dual Climate Controlled Seat Module (DCSM) supplies voltage and ground to both blowers in parallel circuits. If the DCSM detects any of the faults below, the DTC will be set.
- DTC B272E (Driver Ignition Run/Blower Circuit Short to Ground [this DTC sets for an open or short to voltage]) - If either the blower voltage supply or return circuits are open (to both cushion and backrest blowers) or shorted to voltage, the DTC is set and after 4-6 seconds the DCSM disables outputs to the driver seat. The DTC will also set if the blower voltage supply or return circuit is open to only one blower when DCSM supply voltage is less than 12 volts.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- HVAC module
- Backrest or cushion Thermo-Electric Device (TED)
- DCSM
PINPOINT TEST BB: DTC B272E
NOTICE: When taking measurements at Dual Climate Controlled Seat Module (DCSM) harness connectors, do not insert the electrical probes into the female connector pins. Inserting the probes into connector pins can cause intermittent or open electrical connections after reassembly resulting in Diagnostic Trouble Codes (DTCs) and system failure. Touching the tip of these connector pins is recommended instead.
NOTE: The air bag warning indicator illuminates when the correct Restraints Control Module (RCM) fuse is removed and the ignition switch is ON.
NOTE: The Supplemental Restraint System (SRS) must be fully operational and free of faults before releasing the vehicle to the customer.
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BB1 CHECK THE TED BLOWER MOTOR CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in the General
Procedures portion of Restraint Systems.
- Disconnect: Driver Seat Side Air Bag C3051.
- Disconnect: Driver Seat Safety Belt Buckle Pretensioner C3065.
- Disconnect: Passenger Seat Side Air Bag C339.
- Disconnect: Passenger Seat Safety Belt Buckle Pretensioner C3066.
- Disconnect: DCSM C3265C.
- Disconnect: Cushion TED C3035.
- Disconnect: Backrest TED C3034.
- WARNING: Make sure no one is in the vehicle and there is nothing blocking or placed in front of any air bag module when the battery is connected. Failure to follow these instructions may result in serious personal injury in the event of an accidental deployment.
- Connect the battery ground cable. Refer to Battery.
- Ignition ON.
- Measure the voltage between DCSM C3265C, harness side and ground using the following chart.
- Is voltage present on either circuit?
Yes
REPAIR the circuit(s). CLEAR the DTCs. REPEAT the self-test.
DISCONNECT the battery ground cable.
CONNECT passenger seat safety belt buckle pretensioner C3066.
CONNECT passenger seat side air bag module C339.
CONNECT driver seat safety belt buckle pretensioner C3065.
CONNECT driver seat side air bag C3051.
REPOWER the SRS. REFER to Restraint Systems.
No
GO to BB2.
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BB2 CHECK THE TED BLOWER MOTOR CIRCUITS FOR AN OPEN
- Ignition OFF.
- Measure the resistance between DCSM C3265C, harness side and cushion TED C3035, harness side using the following chart.
- Are the resistances less than 5 ohms?
Yes
GO to BB3.
No
REPAIR the circuit(s). CLEAR the DTCs. REPEAT the self-test.
DISCONNECT the battery ground cable.
CONNECT passenger seat safety belt buckle pretensioner C3066.
CONNECT passenger seat side air bag module C339.
CONNECT driver seat safety belt buckle pretensioner C3065.
CONNECT driver seat side air bag C3051.
REPOWER the SRS. REFER to Restraint Systems.
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BB3 CHECK THE RESISTANCE OF THE CUSHION AND BACKREST TED BLOWER MOTORS
- NOTE: The ohmmeter must be connected with the positive lead to pin 2 and the negative lead to pin 4 when measuring. Ohmmeter leads incorrectly connected will result in false readings and lead to incorrect identification of components that are not faulty.
- Measure the resistance between:
- cushion TED C3035 pins 2 and 4, component side.
- backrest TED C3034 pins 2 and 4, component side.
- Are the resistances between 4,000 and 10,000 ohms?
Yes
INSTALL a new DCSM. REFER to Dual Climate Controlled Seat Module (DCSM) Dual Climate Controlled Seat Module (DCSM). CLEAR the DTCs. REPEAT the self-test.
DISCONNECT the battery ground cable.
CONNECT passenger seat safety belt buckle pretensioner C3066.
CONNECT passenger seat side air bag module C339.
CONNECT driver seat safety belt buckle pretensioner C3065.
CONNECT driver seat side air bag C3051.
REPOWER the SRS. REFER to Restraint Systems.
No
If the cushion TED resistance is not between 4,000 and 10,000 ohms, INSTALL a new cushion TED. REFER to Seat Cushion Thermo-Electric Device Seat Cushion Thermo-Electric Device. CLEAR the DTCs. REPEAT the self-test.
If backrest the TED resistance is not between 4,000 and 10,000 ohms, INSTALL a new backrest TED. REFER to Seat Backrest Thermo-Electric Device Seat Backrest Thermo-Electric Device. CLEAR the DTCs. REPEAT the self-test.
DISCONNECT the battery ground cable.
CONNECT passenger seat safety belt buckle pretensioner C3066.
CONNECT passenger seat side air bag module C339.
CONNECT driver seat safety belt buckle pretensioner C3065.
CONNECT driver seat side air bag C3051.
REPOWER the SRS. REFER to Restraint Systems.
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