For the 355, 2.7 brain trust.

On the 348 2.7, the codes simply mean:

1123 - Secondary air solenoid valve relay
2123 - Secondary air solenoid valve

Both are related to the secondary air supplied to the exhaust manifolds and not to any exhaust bypass valve (the 348 does not have it). The 348 does not have an air-pump either so the codes just refer to the LH & RH secondary air systems, thus they can appear on either ECU with the same meaning. These relays and valves normally close the secondary air supply (suction by the exhaust manifolds actually) after 2-3 minutes from the cold engine start.

I do not know whether the 355 2.7 has a similar secondary air system but I believe that the two codes mean the same on the 355 2.7 as what they mean on the 348 2.7.

 

The F355 differs from the F348 in that there is only one secondary air valve on the F355. The pin on the RH ECU which activates the secondary air system relay is the same pin on the LH ECU which operates the exhaust bypass valve.

How the ECUs know that they are Left or Right is another topic (I just started)

My theory is that a programming pin is used to activate different functions/logic on each ECU.

I know some microprocessors are multipurpose, but these two systems have completely different logic. One relies on coolant temperature input, the other on rpms, gear selection, throttle position,...

 

Thanks for the info. The 355 2.7 list of codes (Page C50) does not make any reference to the exhaust bypass valve. Probably just the Ferrari's incomplete info.

 

If the 2123 on the LH ECU was assigned to the bypass solenoid valve (vacuum), it is possible that 1123 in the LH ECU is assigned to the signal from the bypass Thermocouple which verifies that the Bypass Valve has really opened when the bypass solenoid valve opens vacuum to it (and the other way around).

 

Interesting. If there are no codes, it seems that the 2.7 is not even checking the coil of the solenoid valve. I recall from previous discussions that the coil is monitored on the 5.2 for open circuits (but not 100% sure).

 

Has anyone actually seen 2123 on the LH side?

We need a volunteer to disable the solenoid to see if the 2123 message appears.

If it doesn’t, then the appearance of your 1123 will be even more mysterious.

 

According to Ian's earlier post, "The pin on the RH ECU which activates the secondary air system relay (1123) is the same pin on the LH ECU which operates the exhaust bypass valve." In that case, a fault in the coil circuit of the bypass solenoid valve should cause 1123. Code 2123 may not be used at all on the LH ECU.

Ian, is the pin that on the RH ECU operates the secondary air solenoid valve (code 2123) connected to anything in the case of LH ECU?

 

I think you're right, Miro. 1123 is the secondary air system relay.... presumably the relay coil only as the ECU doesn't directly know what the relay contacts are doing.

I think 2123 is misnamed as a "valve" fault. The only way the ECU knows what the valve is doing is by looking at O2 readings. I think 2123 really should include everything else but the relay coil (so that includes the solenoid valve, valve, pump, tubing, check valves, relay contacts, wiring, etc)

Pin 21 on the RH ECU is the one attached to the 2ndary air relay coil. As you say, the same pin on the LH ECU activates the bypass valve solenoid, so this 1123 code must be the equivalent.

The only confusing thing now, is why John's light flashes about the time the car goes into closed loop mode (coolant temperature linked)... and why John has no faults evident with his bypass system.

 

Well, there is no pin for the "valve". I think the secondary air valve message (on the RH side) has to be generated by O2 readings (not changing appropriately to additional air).

The O2 readings will change on the LH side, too, as secondary air feeds both banks. I'm wondering how the LH ECU reacts to this additional air during the warm up cycle (specifically). Does it need to know if the secondary air system has been activated?

 

I don't know if it has any bearing on John's problem., but there are some interesting comments on the Secondary Air System in this thread:

https://www.ferrarichat.com/forum/posts/146023158/

Mitchell says that when the ECU is relearning after a reset, at the end of the warm up cycle, the secondary air system is activated as part of a test (an "intrusive" or "active" test mentioned in Dave Rocks' post).

Is the LH ECU really faulting the exhaust bypass solenoid circuit, or is it reacting to what the secondary air system is doing?

 

For comparison,

In the case of the 348 2.7, there is no ECU pin for the "Secondary air solenoid valve relay" as such relay does not exist so Code 1123 seems not applicable.
The Secondary air solenoid valve (2123) is controlled by the ECU Pin 32 (LH & RH). The "solenoid valve" is actually a vacuum valve that opens vacuum to the vacuum actuated bigger valve that opens the air flow to the exhaust manifold.

Does the 355 2.7 Secondary Air System, in addition to the Air-Pump Relay, also have vacuum solenoid valve(s) that, via vacuum actuated bigger valves, control the flow of (pumped) air to the exhaust manifolds?

 

The electro-pneumatic secondary air "solenoid" valve which is controlled by the ECU allows engine vacuum to go to a pneumatically operated valve. This valve allows the air pump air to go the exhaust manifolds.

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