Checking components
Diagnostic trouble code (DTC) ECM-91DF is stored of the Electronic throttle module (ETM) receives information from the stop lamp switch that indicates that the brake pedal has been depressed, but the Engine control module (ECM) transmits information that the brake pedal has been released. The information that the Engine control module (ECM) transmits, based on the signal from the stop lamp switch. The diagnostic trouble code (DTC) can be stored alone, but it is more common that it has been stored due to no CAN communication with the Engine control module (ECM).
If one or several of the diagnostic trouble codes (DTCs) ECM-901A, ECM-902A, ECM-902B, ECM-911A, ECM-912A, ECM-E000 and/or ECM-E003 are stored at the same time as ECM-91DF, continue fault-tracing according to one of these diagnostic trouble codes (DTCs). If there is another diagnostic trouble code (DTC) in the Engine control module (ECM) that indicates a brake fault, ECM-9400 and/or ECM-914F, this/these must be fault-traced first. Otherwise, continue as follows.
Check, using VIDA vehicle communication, that the Engine control module (ECM) receives the correct information about the status of the stop lamp switch. If the parameter indicates the wrong status, check the signal cable between the brake light switch and the engine control module (ECM) for open circuit, short circuit to ground and short circuit to supply voltage.
Use the diagnostic trouble codes' frozen values as well as the counters, to determine the driving conditions when the problem was detected the first time and how often the problem has occurred. The values show the problem's current status and how intermittent the problem is. If the counters show that the problem has occurred frequently in recent time, it is highly likely that the problem can be recreated during troubleshooting. If the counters show that the problem is extremely intermittent, it is not very likely that the problem can be recreated during troubleshooting.
For markets where upgraded software, released during year 2006 or later, is available, the solution may be to download the upgraded software. As the detection time has increased from 0.3 to 5 seconds, the upgraded software becomes more tolerant towards short intermittent interferences, delays in communication between other CAN connected control modules etc. among other things.
Remedy as necessary.
Other information
Caution! In order for Electronic throttle module (ETM) to reset any reconfigurations as well as delete internally stored problems, the following must be performed:
- Ignition off, wait three minutes so that the main relay / system relay releases the voltage feed to, among other, Electronic throttle module (ETM).
- Then turn on the ignition and turn it off again.
- Wait another three minutes, but if the electric cooling fan is running you have to wait another two minutes after the cooling fan has stopped, to ensure that Electronic throttle module (ETM) is shut off correctly.
If this is not done correctly, diagnostic trouble codes may remain even after deletion of diagnostic trouble codes as well as any reconfiguration, despite the problem being fixed.
- Continue
Refer to Information