P1860 on Pontiac
TCC PWM Solenoid Circuit Electrical
P1860 on Pontiac vehicles indicates tcc pwm solenoid circuit electrical. Au7o has documented this code across 1 Pontiac model — most commonly on Aztek. P1860 is a manufacturer-specific code (most commonly seen on GM vehicles such as Chevrolet, GMC, Buick, and Cadillac) indicating an electrical fault in the Torque Converter Clutch (TCC) Pulse Width Modulation (PWM) solenoid circuit. The PCM/TCM sets this code when it detects a continuous open, short to ground, or short to power in the TCC PWM solenoid valve circuit. This solenoid controls fluid flow that locks up the torque converter, so a fault can affect shift quality, cause stalling at stops, or trigger limp mode. Typical repair costs on Pontiac range from $800 to $4,500, depending on the specific model and root cause.
Common Causes of P1860
- •Failed or shorted TCC PWM solenoid
- •Open, shorted, or corroded wiring in the solenoid circuit
- •Damaged or corroded transmission connector / internal wiring harness
- •Low or contaminated transmission fluid affecting solenoid operation
- •Faulty PCM/TCM or driver circuit
- •Internal transmission valve body / fluid passage problem
P1860 on Pontiac by Model
Pontiac Aztek(1 issue)
- 4T65-E Transmission Failure and Pressure Control Solenoid Erratic Shifting2001-2005
The Aztek's 4T65-E four-speed automatic suffers from pressure control (force motor) solenoid failure that drives line pressure to maximum, causing harsh shifting and accelerating internal wear; GM addressed related harsh-shift complaints in TSB 02-07-30-022B (faulty transaxle connectors, 2001-2004) and cold-weather reverse servo seal shrinkage in TSB 04-07-30-028. NHTSA complaints for the 2003 Aztek document gear failure, no-forward-movement, and shifter problems at an average of about 157,000 miles. Left unaddressed, the harsh-shift condition commonly progresses to slipping and loss of 3rd/4th gear requiring a rebuild or replacement.
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View P1860 across all makes →Frequently Asked Questions
What does P1860 mean on Pontiac?▼
P1860 stands for "TCC PWM Solenoid Circuit Electrical." P1860 is a manufacturer-specific code (most commonly seen on GM vehicles such as Chevrolet, GMC, Buick, and Cadillac) indicating an electrical fault in the Torque Converter Clutch (TCC) Pulse Width Modulation (PWM) solenoid circuit. The PCM/TCM sets this code when it detects a continuous open, short to ground, or short to power in the TCC PWM solenoid valve circuit. This solenoid controls fluid flow that locks up the torque converter, so a fault can affect shift quality, cause stalling at stops, or trigger limp mode. On Pontiac specifically, this code is documented across 1 model.
What causes P1860 on Pontiac vehicles?▼
Common causes on Pontiac: Failed or shorted TCC PWM solenoid, Open, shorted, or corroded wiring in the solenoid circuit, Damaged or corroded transmission connector / internal wiring harness, Low or contaminated transmission fluid affecting solenoid operation, Faulty PCM/TCM or driver circuit. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P1860 on a Pontiac?▼
Repair costs on Pontiac range from $800 to $4,500, depending on the specific model and root cause.
Which Pontiac models have P1860 documented?▼
Au7o has documented P1860 on 1 Pontiac model: Aztek.