A friend of mine drives a 2002 Oldsmobile Bravada with a 4.2L engine. The other day, after taking the highway on his way to work and reaching a speed above, 40 or 50 mph, all the gauges on the instrument panel when down to zero: speedometer, tachometer, temperature, charge indicator, etc. However, the engine did not die. It went to idle and he was able to coast to the shoulder of the road.
Strangely enough, depressing or pumping the accelerator did not rev up the engine or seem to have any effect. The engine was not responding to the pedal, but there did not seem to be any mechanical problem between the pedal and the throttle linkage.
Once he pulled out of the road and shifted to Park, the engine responded again to the accelerator pedal and he was able to go back on the road.
However, once he reached a speed above 40 or 50 mph, the same thing happened again. And again. He was able to get to work and back home driving below 40 or 50 mph.
We connected a code reader to retrieve any trouble codes from the computer but there were none.
He believes the problem might be related to the alarm system that was installed a few weeks ago.
Any suggestions or ideas to troubleshoot this problem?
There is a Service Bulletin on this problem. This is it below.
Bulletin No.: 01-07-30-002E
Date: September 23, 2005
Malfunction Indicator Lamp (MIL) On, Transmission Stuck in Second or Third Gear, Instrument Cluster Inoperative (Verify and Repair Source of Voltage Loss In Transmission Solenoid Power Supply Circuit)
2006 and Prior GM Passenger Cars and Light Duty Trucks
2005-2006 HUMMER H2
2006 HUMMER H3
2005-2006 Saab 9-7X
with 4L60-E, 4L65-E, 4L80-E or 4L85-E Automatic Transmission (RPOs M30, M32, M33, MT1, MN8)
This bulletin is being revised to update model years, add additional models and add additional diagnostic information. Please discard Corporate Bulletin Number 01-07-30-002D (Section 07 - Transmission/Transaxle).
Some customers may comment on one or more of the following conditions:
The Malfunction Indicator Lamp (MIL) is ON.
The transmission is defaulted to second gear (4L80/85E).
The transmission is defaulted to third gear (4L60/65E).
The instrument cluster is inoperative.
Upon investigation, one or all of the diagnostic trouble codes (DTCs) P0740, P0753, P0758, P0785, P0787, P0973, P0976, P1860, P2761, P2764 and P2769 may be set depending on the vehicle.
The most likely cause of this condition may be a loss of voltage to the transmission solenoid power supply circuit. This condition may also be the result of an incorrect installation of an aftermarket electronic device such as a remote starter or alarm system.
Important: If the vehicle is equipped with an aftermarket electronic device and the DTCs are being set when the device is being used, verify that the appropriate fuse is being supplied battery voltage during operation. If voltage is not present at this fuse, these DTCs will be set due to lack of voltage at the solenoids. This condition is most likely to occur with an incorrectly installed remote starting system. If this is the case, refer the customer to the installer of the system for corrections. ANY REPAIRS DUE TO AFTERMARKET INSTALLATION OF ACCESSORIES IS A NON-WARRANTABLE ITEM.
With the ignition switch in the RUN position, test for battery voltage at the circuit fuse in the transmission solenoid power supply circuit information. Refer to the appropriate Service Information Document for the transmission solenoid power supply circuit information.
If the battery voltage is present at the fuse, inspect the ignition voltage circuit between the fuse and the transmission for possible opens.
If the battery voltage is not present at the fuse, test for continuity between the fuse and the ignition switch. If NO continuity is between the fuse and the ignition switch, repair the open in that circuit.
If you have continuity between the fuse and the ignition switch, the most likely cause is the ignition switch. Replace the ignition switch using the appropriate Ignition Switch.
Having the shop that installed the alarm system check their installation to be sure they have not tapped into the wrong power source and they used the proper grounds for the system. If all is installed correctly then proceed with this Service Bulletin to have the Ignition Switch replaced.
I hope this information is helpful.