The full utilization of diagnostic Scantools as a source of diverse and certainly the necessary data when troubleshooting a wide variety of troubleshooting is a crucial condition for the rapid and high-quality repairs.
Many topics of our forum, you can find examples of effective analysis of the so-called "stored data» (Freeze Frame Data). The essence of the set of data that records ECM values in time of confirming a malfunction. In the modern cars are stored data of five counts time (Figure 1). Sometimes these data can speed up the process a lot of diagnostics and improve its quality.
Another source of information is very useful service bulletins (TSBs), in which automakers describe how to resolve newly discovered "factory" problems. Read more about them, see. In http://alflash.com.ua/tsb.htm (Russian).
Another important source of information is a reputable web forums, archives contain thousands of descriptions of successful repairs. Familiarity with their materials is very interesting not only in terms of recurrence of the situation, but also useful for the expansion of practical experience.
The history of «Toyota P0606-Don't replace the ECM», described in message on the conference iATN our colleague Robert from Massachusetts - a compelling illustration of the thesis and the reason for this article.
That's how Bob describes the situation with Toyota Camry LE (3.5L) 2007MY. The customer complained about the unfading light MIL. The first time he saw the car in connection with the need to re-flash the ECU (TCM) according to the bulletin of Toyota (T-SB-0089-09). Reprogramming went well, but after a month happened inclusion of the malfunction indicator in the engine running. This is stored in the memory of ECM fault code DTC P0606 (ECM /PCM Processor). His description of the repair in the manual (RM0250U) recommended in this code and in the absence of other fault (P0136, P0137, P0138, P0156, P0157 or P0158) replacement ECM.
Bob decided not to hurry with the replacement, and turned to the study archive Forum iATN (International Automotive Technicians Network).
There he found a message Chris Meyering (Abbottstown, Pennsylvania, USA) 2009 on the troubleshooting P0606 in the Toyota RAV4 3.5L (2006MY). In the car, after the "dealer" service shop avail replaced ECM, the code is still being written in his memory. Chris then check the voltage H02S (B1S2) and found that changes the voltage of the oxygen sensor at moving its wiring.
Bob repeated this test with the help of Snap On Verus Pro received the result - in the "wiggling" wiring detected intermittent "failure" of the oxygen sensor voltage O2S B2S2 (Figure 1) while the "jump" the value of its parameter "resistance» (Impedance). Due to the short duration of the DTC sensor glitch not fixed.
Technician Harvey from Vancouver added a quote from the subject of the Toyota service bulletin, which directly connects the code with the possible malfunction of the oxygen sensor (Figure 2).
In addition, Harvey said that in his practice often repair code P0606 has been caused by a malfunction (internal sensor breakage) of conventional oxygen sensor downstream of the catalyst.
As an example, these screens have been brought Toyota RAV4 3.5L (2007MY) DTC P0606 and "wandering" malfunction (Intermittent Problem) O2S B1S2 (Figure 3). The graph clearly shows how spontaneous and randomly changes the parameter «O2S Impedance S1B2» of the RAV4.
In our practice, also I met this DTC. For example, in the topic of our forum participant MakNathal (Rovno) is an example of the relationship of code DTC P0606 to malfunction wideband Air/Fuel Ratio Sensor.
I caught Lexus ES350 (3.5L) 2007 model year in the memory of the engine ECU which "sat" code P0606 and the owner was ready to buy another unit.
Mandatory checks "saved data" (Figure 4) immediately showed abnormal value "O2S Impedance B2S2". The valid range of this parameter is shown in Figure 5. Replacing sensor B2S2 fixed the problem and avoid unnecessary costs.
It should be added that sometimes it is not so simple. For example, the Camry and Solara (2003-2004MY) with engine 2AZ-FE Toyota has released a service bulletin (TSB EG051-04), according to which in the case of DTC P0604, P0606 and / or P0607 should be replaced ECM. A similar measure is recommended for the Toyota Corolla and Matrix with 1ZZ-FE engine (TSB EG042-07).
We express our appreciation to Robert and Harvey for the information and for permission to use their screeshots.
V. Leshchenko, 2015
Полный текст этой заметки на русском языке (The full text of this article in Russian)