Code result
P0899
Transmission Control System MIL Request Circuit High
Moderate severity
What it means
Voltage on the transmission control system MIL request circuit is above the expected window. Wire shorted to B+ or driver open.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Wire shorted to B+
highOne of the most commonly reported causes for this code — check this first.
Driver fault open
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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