Faulty Signal. Intermittent Fault
Faulty signal
Frozen values and counter for diagnostic trouble codes.
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. Driving conditions may be, e.g., if the engine was running, what speed the vehicle had, or how long the driving distance was.
Counter
The counters are used to determine the problem's status. For general information about the counters, see: Counters, description Counters, Description
Counter 1 indicates the number of drive cycles without fault since the fault was last validated.
If counter 1 is the same as 0, this means that the fault has been detected in this operating cycle (permanent fault). If no troubleshooting or repair has been performed in the vehicle in this driving cycle, the problem is probably in the vehicle.
If counter 1 is over 0, this indicates that the problem has not been detected in this driving cycle (intermittent problem). The problem has existed earlier but is not active right now.
Then check counter 4. Counter 4 indicates number of driving cycles with problem since the problem was validated for the first time.
If the number of driving cycles with problems is high, this indicates an intermittent recurring problem, which means greater possibility of regenerating the problem in the workshop.
If the number of driving cycles with problems is low, this indicates an intermittent temporary problem, which means small possibility of regenerating the problem.
Hint: Counter 3 indicates number of driving cycles since first time that the problem occurred. If the value for counter 3 is divided by the value for counter 4 , the intensity of the problem is obtained. The higher the value, the higher the problem intensity. A high problem intensity indicates that the malfunction recurs often.
Counter 5 can be used for more exact determination of when the problem occurred. To compare counter 5 for diagnostic trouble codes indicates in which order the diagnostic trouble codes were stored.
5-cyl. non-turbo engines
For model year 1999, only counter 1 and 2 are available.
Frozen values
The frozen values show the driving conditions when the control module detected the problem the first time. Check using the frozen values that the diagnostic trouble code has not been caused accidentally during troubleshooting of the vehicle. If the driving distance is 0 km/miles, this indicates that the problem has occurred at the control modules' start-up of the CAN-net, when reception of a relevant value has not been possible. This also applies to other values that come via the CAN-network. In these cases, counter 5 can be used to determine when the problem was generated.
If the diagnostic trouble code has been caused during this troubleshooting, it may be due to, e.g., disconnected component, too low or high battery voltage, or that some control module has been disconnected.
If the diagnostic trouble code has been stored since before, there has likely been a problem or interference, which has resulted in the control module detecting a problem.
For general information about frozen value, see: Information Information
For information about frozen values.
- Turbo engines and 6-cyl. non-turbo engines: Description of frozen values Me7 Description of Frozen Values ME7
- 5-cyl. non-turbo engines: Frozen values DENSO, description Description of Frozen Values DENSO
Read off the diagnostic trouble code's counter and frozen values by clicking on the symbol for VCT2000. Choose diagnostic trouble code in question.
Continue - DONE
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DONE - Checking components
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Checking components
Check, using the diagnostic trouble code (DTC) statuses, if the fault is intermittent or permanent.
Permanent fault
Check the cable between engine control module (ECM) terminal #B25 and accelerator pedal position sensor terminal #2 for open circuit, short circuit to supply voltage or short circuit to ground depending on the type of fault detected. In conjunction with this, check the cable between engine control module (ECM) terminal #A56 and electronic throttle module (ETM) terminal #1 since #B25 and #A56 are internally connected in the engine control module (ECM) and a short circuit on #A56 will generate this diagnostic trouble code.
Intermittent fault
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. The operating conditions can be, for example, whether the engine was running, what the speed of the vehicle was and what the battery voltage in the system was. This information can facilitate searching for an intermittent fault.
Check whether the engine control module (ECM) has stored any other diagnostic trouble codes that indicate a fault in the pulse width modulated (PWM) signal from the accelerator pedal position sensor. If trouble code ECM-9520, Faulty signal, is stored together with ECM-985F and ECM-9180, but ECM-959F is not stored, one can assume that the fault occurred for more than 0.05 seconds but less than 0.1 seconds.
If ECM-9180 is stored together with ECM-9520 Faulty signal and ECM-958F, one can assume that the fault occurred for more than 0.1 seconds but less than 0.4 seconds.
If ECM-959F is stored together with ECM-9520, Faulty signal, ECM-9180 and ECM-958F, one can assume that the fault occurred for more than 0.4 seconds.
If diagnostic trouble codes ECM-9520, ECM-9180 and/or ECM-958F occur together with diagnostic trouble codes that indicate an electrical fault in the injectors, EVAP valve and/or turbo control valve, it indicate that there may be a problem with the 12-volt supply from the system relay. Use the diagnostic trouble code's frozen values and the counter to determine if the fault may have been stored at the same time.
Hint: Using VIDA vehicle communication, check that the parameter "Accelerator pedal, PWM" indicates correct values. There are other parameters that can be of help when fault tracing and verifying this diagnostic trouble code. To aid fault tracing, use Component specifications when measuring and checking relevant components and use Wiring diagram , Signal description and Breakout box to measure and control signals to and front the control module or its components.
For markets where upgraded software, released during year 2006 or later, is available, the solution may be to download the upgraded software. Since detection time has been increased from 0.05 to 0.7 seconds, the upgraded software will be more tolerant to short, intermittent disruptions.
Remedy as necessary
Other information
- To connect the breakout box, see Connecting the breakout box, B5234T9, B5244T7 Connecting The Breakout Box.
- To access/replace the accelerator pedal (AP) position sensor, see Replacing the accelerator pedal module Removal and Replacement.
- For information about signals, see Signal specification Signal Specifications.
- Checking wiring and terminals Checking Wiring and Terminals
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. If the electric cooling fan is running, you have to wait another two minutes after the electric cooling fan has stopped, to make sure that Electronic throttle module (ETM) has been shut off correctly.
If this is not done correctly, diagnostic trouble codes may remain even after deleting diagnostic trouble codes and any reconfiguration may remain, despite the problem being fixed.
Continue - Fault-tracing information
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Fault-tracing information
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