Several Network Communication DTCs
I need help on this 08 Lexus RX 400 hybrid. I have a lot of data line communication I have the 60 ohms and the 2.5 volts on pin 14 and 6 , I do not have good information of flow chart more than check resistance o wiring.
I do have communication with the scanner to each individual module
I have some screen shots as well a wave form as I and not expert on network some thing call my attention at the end of data line package there is spike .
engine dtc: U0001 High speed CAN communication bus state : current
Hybrid control 9 dtc : P0A1D Hybrid power train control module current
U0100 lost communication with ecm/pcm 'A'
U0129 lost communication with brake control system control module
U0131 lost communication with power steering control module
U0146 lost communication with gate way "A"
abs dtc: C0205 front wheel speed sensor LH circuit
U0073 control module communication bus off
U0123 lost communication with yaw rate sensor module
U0126 lost communication with steering angle sensor module
B1281 air bag ecu communication stop
THE FOLLOWING WAVEFORM WAS TAKEN AS VEHICLE CAME IN
I did a hard reset by touching battery terminal , road tested 10 miles in about 6 miles the dtc came back the vehicle does not experience any driveability issues . the next capture was taken after hard reset.
Is their another number after the P0A1D code? Like P0A1D 134 or something?
The P0A1D DTC should have a 3 digit INF code as part of it e.g. P0A1D-144. Regardless of the INF code, DTC P0A1D indicates an internal error within the HV power management ECU, and replacement of this ECU is required if this DTC is reoccurring. The HV power management ECU monitors its own internal operation and will set this DTC and go into a fail safe mode when it detects a malfunction.
thank you for your help
I did not see it a sib_ code but I am scanning with the launch, I will scan with tech stream now
Well looks like you are right, after reading and doing some research they are truly one unit.
Question where was the wave forms taken. Which data lines?
pin 14 and 6 at DLC connector.
Their is also a pin #5 Violet & #13 brown. I'm not sure what those do but they are on a network. SO I would have to somewhat assume they should have some sort of communication wave form. WOuld I be correct that you have checked the voltages and grounds at the HV/ECM ? Forgive me I have not had a network problem on these vehicles before. So even though the chart does say replace this module I…
thanks , having all this bunch of dtc I am having issues to organize and where to start as which modules is responsible for dropping the network, clear dtc ,after the second road test got back those dtc except the P0a1d
The P0A1D didn't return?
Not that one did not return
Okay I'm not sure where you are on you diagnostics but what codes have returned so far? You said you could communicate with all modules. And no run ability problems to note?
the dc for communication are returning all over , the P0A1D hast not returned. I have that vehicle on the sidefr now
Hi Joel, I agree the approach is to analyze the DTCs and overlap what we know there with schematics. Did not find anything in Alldata for your Lexus (not a power Alldata user so perhaps there are OE schematics there) but did spend a few minutes pouring over the 2 page data line schematics in Mitchell / Shopkey. Here's what I've observed; 1. There are two modules setting communications related…
thank you dave , big fan of your training material at AVI
David said it better then I could over a forum. And he did it without asking any questions.
Looks like you have a module putting out bad data, see the spikes dropping below 1 V on can low and going over 4V on can high? Thats no good, keep the vehicle running while monitoring this network also make sure that this vehicle does not have a diagnostic can if so you can not check at the dlc connector, I say this cause I noticed the dtc U0146 “Lost comm with gateway A”