PINPOINT TEST D : TCS (Tow Haul)
- D1 RETRIEVE AND RECORD ALL DTCS
- Using the diagnostic scan tool, retrieve all DTCs.
Is DTC P1780 present?
Yes GO to D2. No No trouble found with the TCS system. REFER to Instrumentation, Message Center, and Warning Chimes if the Tow Haul lamp does not illuminate. - D2 CHECK THE BCM FUSE
- Ignition OFF.
- Remove the BCM fuse 41 (7.5A).
- Check BCM fuse 41 (7.5A).
Is the resistance less than 3 ohms?
Yes GO to D6. No GO to D3. - D3 CHECK THE BCM FOR AN INTERNAL SHORT
- Disconnect: BCM C2280B .
- Inspect for damaged or pushed-out terminals.
- Install a new fuse.
Did the fuse fail?
Yes INSTALL a new BCM. REFER to Multifunction Electronic Modules . No GO to D4. - D4 CHECK THE TCS POWER CIRCUIT FOR A SHORT TO GROUND
- Disconnect: Center Stack C2114 .
- Measure:
Positive Lead Measurement / Action Negative Lead C2114-8 Ground
Is the resistance greater than 10, 000 ohms?
Yes GO to D5. No REPAIR the circuit. - D5 CHECK THE TCS SIGNAL INPUT CIRCUIT FOR A SHORT TO GROUND
- Disconnect: TCM C1750 .
- Measure:
Positive Lead Measurement / Action Negative Lead C2114-4 Ground
Is the resistance greater than 10, 000 ohms?
Yes GO to D6. No REPAIR the circuit. - D6 CHECK THE TCS POWER CIRCUIT FOR AN OPEN
- Disconnect: Center Stack C2114 .
- Disconnect: BCM C2280B .
Is the resistance less than 3 ohms?
Yes GO to D7. No REPAIR the circuit. - D7 CHECK THE TCS SIGNAL INPUT CIRCUIT FOR AN OPEN
- Disconnect: TCM C1750 .
Is the resistance less than 3 ohms?
Yes GO to D8. No REPAIR the circuit. - D8 CHECK THE TCS
Is the resistance less than 3 ohms with the switch pressed and greater than 10, 000 ohms when released?
Yes INSTALL a new TCM. PROGRAM the TCM with the latest calibration level. PERFORM the Solenoid Body Strategy Download procedure. REFER to Automatic Transmission - 6F35 . No INSTALL a new tow haul switch. REFER to Tow/Haul Switch .
