P1811 on Saturn
On GM vehicles (Chevrolet, Buick, Saturn): maximum adapt and long shift
Severity: Inspect soon
GM bulletins tie P1811 to slips, flares, harsh shifts, launch shudder and a lit service lamp, so the transmission should be checked soon. We found no GM source on whether it is safe to keep driving.
It gets more serious if:
- Not verified: The transmission goes into limp-home mode (stuck in one gear, little power) or the vehicle will not move. Regulations require the light in limp-home mode, but we found no source saying whether you must stop
This page covers only what differs on Saturn. For what P1811 means, the ranked causes and the test order, see the P1811 guide.
What's different on Saturn
SaturnYour car
2000–2004
Supported by vehicle dataSaturn and GM bulletins 02T84 and 04-07-30-020 cover the service lamp with P1811 on L-Series cars. The bulletin is on NHTSA, but whether it is still current is not verified, so it is labelled vehicle data rather than confirmed.
02T84Status unverified
Service wrench lamp with P1811 maximum adapt and long shifts
2000ls · issued · NHTSA 10000382
Only the NHTSA flat-file summary was read, not the bulletin itself.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
04-07-30-020Status unverified
Service vehicle soon lamp with P1811 maximum adapt and long shifts
2001–2004ls, l200, l300 · issued · NHTSA 10006645
2001–2002 LS, 2003 L200, 2004 L300. Only the NHTSA flat-file summary was read, not the bulletin itself.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
Sources and review
- Saturn 02-T-84: service wrench lamp with P1811 maximum adapt and long shifts
- GM 04-07-30-020: Saturn L-Series service lamp with P1811 maximum adapt and long shifts
- GM 00-07-30-002B: slips, harsh shifts, shudder with P1811 or P0748
- GM PIP-4651: 4T45 soft or erratic shifts, P1811
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error