P1520
Transmission Range Switch Circuit
What it means
P1520. Transmission Range Switch Circuit. This Chevy-enhanced code applies to Silverado, Sierra, Tahoe, Impala, Malibu.
Findings, check these first
- Misadjusted or worn park/neutral position switch on 4L60-E equipped vehicles
- Corroded transmission range connector from road splash
- Stretched shift cable preventing full engagement of the manual valve detent
- Faulty ignition switch back-feeding the range signal circuit
Standard procedure
- Verify the gear indicator on the scan tool matches the actual shifter position in every detent
- Inspect and adjust the shift cable and range switch alignment first
- Clean the transmission range connector and check for transmission fluid wicking into the harness
- Replace the range switch only if the scan tool reading disagrees after adjustment
Look up another code
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Sources and review
Review: no source links are recorded for this entry.
Last updated 2026-09-13.
Report a correction for P1520. Include your vehicle, the issue and a source if you have one.