Hey all, new to the forum, but not to equipment repairs. But this Volvo has me confused. Operator parked it for the night, went back in the morning, a brisk -30 here in Canada. And called me for a no start. Displays "communication failure" can communicate and pull codes from VECU, EECU, IECU. Only common code is psid 203 fmi9. Which my service information is so generic. It will start and operate in manUal mode. But no matter what I do the keypad is dead in the water. Cannot operate the IECU. I ran it onto the lowbed and back to the shop in manual mode. I've been trying to utilize the wiring diagrams previously posted on other threads. But no success. A proper diagram, troubleshooting tree and maybe some insite would be much appreciated. 2013 VOLVO EC250DL VCEC250DK00210302
Please check out the attachments. Sch 2 focuses on I-ECU Later attachments will show supporting diagrams.
Sch 1 shows path of power from batteries through switches and relays leading to sch 2. Hope this is helpful. In the past, a member had a comms issue. I seem to recall something about a corroded data ribbon. I can't remember the members handle. Good luck.
Thanks for all the info I'll get back into it this afternoon, where are the terminating resistors located on the can bus. I have 140ohm and. 65 ohm across each pair at the keypad. I'm wondering if I'm missing the other half because of the keypad being unplugged. Or because of another issue. Thanks again
Typical CAN resistance is 60 ohms with both plugged in and 120 each when measures separately. It sounds a touch high at 140. I would check all your connections for corrosion or loose terminals. Harness layout should give you a ballpark idea of where to look.
Went through every wire, checked continuity from ecu to ecu, load tested each wire. All came back good, took a chance and replaced the key pad, for the tune of $2700.. and its all working again. Why would something as simple as an operators keypad inhibit the use of the machine. Either way, the machine is working again. Thanks for the information, made my life much easier.