'SERV. VEHICLE SOON' LIGHT/ 'GEAR SELECT PROBLEM' MESS.
SUBJECT: "SERVICE VEHICLE SOON" LIGHT OR MESSAGE OR "GEAR SELECT PROBLEM" MESSAGE, CODE E91/E091
MODELS AFFECTED: 1991-1992 DE VILLES, FLEETWOODS, ELDORADOS, AND SEVILLES
This bulletin supersedes bulletin T-92-56A which should be discarded. Ground repair procedures and the warranty statement have been revised.
Some vehicles may experience a "Service Vehicle Soon" light or a "Gear Select Problem" message (Eldorado/Seville) with a code E91 or E091. This code may result in inoperative cruise control. The vehicle continues to start only in park or neutral.
These conditions may be caused by a Neutral Start Back Up (NSBU) switch (or a loose or corroded engine or chassis ground). To repair this condition use the following procedure:
1. Enter ECM diagnostics and record the code E91 snapshot data. Pay particular attention to parameter L.0.7 on DeVilles and Fleetwoods and ED10 on Eldorados and Sevilles. If the code data indicates battery voltage below 13.O with the engine running, proceed to step 2. If the voltage is 13.0 or above, proceed to step 3.
2. 1991 Eldorados and Sevilles - Remove and clean ground G103 located by the starter (refer to page 8A-201 - 1, Figure C, in the Service Information Manual for location):
a. Remove the two starter bracket nuts, cable, starter bracket mounting stud, and starter bracket.
b. Discard the starter bracket mounting stud and the starter bracket.
c. Clean both the eyelet and the engine block in the area where the starter bracket was located with a wire brush.
d. Install a new starter bracket, P/N 3538914, with the eyelet between the block and the bracket. Bend the starter bracket as necessary to provide clearance between the block and the bracket for the eyelet.
e. Install a new starter bracket mounting stud, P/N 3537885, to the block. Torque to 38 Nm (27 lbs. ft.).
f. Install the nut that secures the starter bracket to the starter. Torque to 3.0 Nm (27 lbs. in.).
o Continue to step 3.
1992 Eldorados and Sevilles - Remove and clean ground G301 on the right-hand kick panel (refer to page 8A-201-23, Figure A, in the Service Information Manual for location):
a. Remove cables and nut(s) from sheet metal ground stud.
b. Clean stud and eyelets with a wire brush to remove paint, corrosion, or rust.
c. Install cable eyelet(s), largest to smallest, with the largest eyelet against the fender.
d. Install one nut and torque to 9 Nm (6.6 lbs. ft.).
o Continue to step 3.
1991-1992 DeVilles and Fleetwoods - Remove and clean ground G101 located by the starter (refer to page 8A-201-1, Figure C, in the Service Information Manual for location):
a. Remove the starter bracket mounting stud to the block, the nut that secures the starter bracket to the starter, and the starter bracket.
b. Discard the starter bracket mounting stud and the starter bracket.
c. Remove the ground cable located at the motor mount.
d. Clean both the eyelet and the engine block in the area where the starter bracket was located with a wire brush.
e. Install a new starter bracket, P/N 3538914, with the eyelet between the block and the bracket. Bend the starter bracket as necessary to provide clearance between the block and the bracket for the eyelet.
f. Install a new starter bracket mounting bolt, P/N 3537885, to the block. Torque to 38 Nm (27 lbs. ft.).
g. Install the nut that secures the starter bracket to the starter. Torque to 3.0 Nm (27 lbs. in.).
o Continue to step 3.
3. Replace NSBU switch with P/N 1994335 with a date code of 7092 (July 9, 1992) or higher for DeVilles and Fleetwoods and P/N 1994334 with a date code or 8142 (August 14, 1992) or higher for Eldorados and Sevilles. Refer to Section 7A1 in the appropriate Service Information Manual for replacement procedure. To identify the date code refer to Figure 1.
4. Verify repair by performing PCM code E091 diagnosis as specified in Section 6EA of the appropriate Service Information Manual.
NOTE: Do not adjust the shift indicator needle linkage (K5243) to correct a code E91.
Parts are currently available from GMSPO.
For warranty purposes use Labor Operations T6687, T6688, and T6689 if ground repair is required. Use Labor Operation J6383 for Neutral Start Back Up switch replacement.
WARRANTY INFORMATION VEHICLE SERIES -------------------- Operation -------------- Operation Description Number C D E K V --------------------- --------- -------------------- Switch, Park/Neutral Replace J6383 1.1 .6 .6
Clean and Tighten Grounds
1991 - 1992 C grounds by starter* T6687 .7
1991 E/K grounds by starter* T6688 .9 .9
1992 E/K grounds by RH kick panel* T6689 .4 .4
* Labor time includes performing idle learn procedure.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.
