* Power Steering Pump and Electrical Demand: The power steering pump in these vehicles is electrically assisted (or potentially even fully electric, depending on the specific trim). When you turn the wheels, the pump draws significant electrical current. If there's a problem in the electrical system, such as:
* Weak or failing battery: The sudden high demand of the power steering pump might overwhelm a weak battery, causing a voltage drop that shuts down the engine's computer (PCM) to prevent further damage.
* Alternator problems: A failing alternator might not be able to keep up with the increased electrical load, resulting in the same voltage drop and engine shutdown.
* Faulty wiring or connectors: Corrosion, loose connections, or damaged wiring in the power steering system's circuits can lead to intermittent electrical failures, particularly under stress (like when turning the wheels).
* Power Steering Control Module (PSCM) issues: The module that controls the power steering pump might be malfunctioning, leading to erratic behavior and potentially causing the engine to stall.
* Other possibilities (less likely given the circumstances):
* Crankshaft Position Sensor (CKP) or Cam Position Sensor (CMP) issues: While these sensors are critical for engine operation, a malfunction would typically cause problems regardless of steering wheel position. The fact that it only happens when turning suggests a power draw-related issue is more probable.
* Grounding problems: Poor grounding in the electrical system can lead to voltage fluctuations and component failure.
Troubleshooting Steps:
1. Battery Test: Have the battery and charging system (alternator) thoroughly tested at an auto parts store or mechanic. A load test is especially important to check the battery's ability to handle high current demands.
2. Visual Inspection: Carefully inspect the power steering pump, its wiring harness, and related connectors for any signs of damage, corrosion, or loose connections. Pay close attention to the connections at the battery terminals as well.
3. Professional Diagnosis: Given the complexity of the issue, it's highly recommended to take the Escalade to a qualified mechanic or dealership. They have the diagnostic tools to check for voltage drops, fault codes (stored in the PCM), and properly test the power steering system's electrical components.
Ignoring the problem could lead to more serious issues and potentially leave you stranded. It's best to get it diagnosed and repaired promptly.
