430 430 challenge can bus issue

Working on a 430 challenge. issue began with losing some of the data on the marelli dash, engine losing power, ASR turning off. Scan found no communication with cluster or Abs unit, P0600 Can faulty in the trans, no faults in the engine modules. Fuses are good, check of C can found 60 ohm resistance, 2.5 volts high, 2.3v low. Need accurate diagram for challenge car as OBD connector has the B can wires in #6 and #14, not white and green C can wires as shown in the coupe diagram. Have disconnected all units one by one , still no bus communication, suspect ecms and trans communicating over K diag wire.

 

Issue has now progressed to the engine no longer starting, no faults in ecms,

 

Thank you for your assistance. Battery and alternator are good. The can bus layout on these Ferrari vehicles are nothing like the wiring diagram indicates. No green and white wires. Terminals 6 and 14 have white/pink and black/pink. These traced to the 8 pin harness on the cluster. The green and white of the C bus go into the 12 pin connector on the cluster. Test of C bus with scope shows a normal bus operation. 2.5v high, 2.3 v low with normal waves appearing. Did not scope the OBD as my scope acted up, I think due to hot conditions in the shop, but with switch on have 0.07 on one bus wire and 4.95 on the other wire. Have a 360 here in the shop. It has 0.07 on one side and 10.5 on the other. Wire color there is also not green and white, but not the same as the challenge car. As far as the no start condition, have no fuel pump activation, I suspect tied to the can bus issue not allowing relay to engage. The 430 coupe diagram is so much different than the real world challenge car. I was suspecting the cluster as the issue, Dont really know. This morning i disconnected the cluster completely. i could still talk to the ecms and transmission though some Ferrari magic. Have a California and a 488 here also, going to check the OBD outputs on those as well to begin developing a database.

 

As a side note, the wiring diagrams show the B can wires as being in OBD connector ports 1 and 9. nothing there.

 

I have cranking, I do have a challenge car service manual that shows a immobilizer relay. No inertia switch I can find. Check of this relay found activation power coming from the right ecm with the key on. There is nothing on the 30 power terminal coming into the relay. according to the coupe diagram it should be coming from terminal 43 of right ecm, however, that wire is the wrong color and does not ohm out to the relay. Sure wish I could find a true challenge car diagram. so many things different.

 

The relay and fuse boxes all look the same as the regular 430. Most all spots have relays, I find this kinda strange as so many systems are missing from a race car. Even the ABS unit is unique. Only has a 29 pin connector. I agree, time to trace and create my own wiring diagram. What would be the best tracer tool in your opinion.

 

That is the relay. With the ignition switch flipped on there is power and ground on pins 1 and 2 . With the RH ecm disconnected There is no longer power supplied to pin 1. And check between pin 3 and 43 has no continuity. Getting a tracer coming.

 

I noticed on the coupe 430 wiring diagram, section fd0101, in the B can wiring that there are very faint numbers visible at the obd connector that say 6 and 14. I wonder if these denote challenge car wiring. Not there in the C can diagram, however, faint numbers exist at the cluster connection, cant make those out. I am beginning to think the fuse and relays listed in the challenge WSM are just there in the factory harness and do not control things.

 

I would agree that the challenge should just operate on an immobilizer delete setup for the ecu, however, these things have the relay 183662. That relay has power and ground with the ignition switch flipped, activating the relay. have a led test light that shows power and ground to test and nothing appears on the other legs of the relay. Is any signal sent readable or only seen on a scope? I can talk to each ecm, no faults found, however, there is no ground signal sent from pin 65 on the right ecm to the PDR8 relay activating the pump relay. Have not tested the left side, but I am sure the right ecm turns on the left ecm immobilizer system to allow pump operation. Seems just like you didnt press the magic button on the key properly before starting.

 

This thing has the magnetti data aquisition dash installed. That appears to be tied to the B can of the car so no symbols available. continued checking of the PDR1 relay found at the moment of ignition turn on approx 100mv then nothing. check of the 30 and 87 pins then found approx 11.5 volts on both with meter, but this will not light up the led test light. hit the start button and boom, she started. missing gear indicator, fuel oil temp on the dash. Shut off and started again. Then shut off master switch, waited a few and tried again. Will not start. Right ecm not activating fuel pump relay. I am now switching to diag of the loss of can bus as the likely cause. I can always talk to both ecms when connected and the trans. Ecms say no faults. I disconnect the car side connector on right ecm and check faults. No faults in left ecm, seems strange. Hard fault in trans for p0600, can issue. Disconnected the car side of the trans ecm. Left the ecm disconnected also. Scan now finds communication with the cluster showing faults for can bus, abs, various engine readings. Tries to duplicate the cluster communication unsuccessful. Disconnect the abs,now I have cluster comm. Keep in mind I can never comm with the abs unit.

 

I am beginning to suspect I have internal issues with the right ecm.