Code 1.4.4 flashed – “no load signal to LH control unit”"

[Clifford Pope]

1993 LH Jetronic 2.4

The light suddenly came on, but the engine continued to run perfectly, and restarted several times later in the day.
I checked in socket 2 (no faults) but in socket 6 it flashed 1.4.4. Just out of curiousity I cancelled it, and it has not so far re-appeared.
Is this an indication that something might be faulty, or just one of those blips that can be ignored? Supposing the code came on but stayed on, what would it mean?

Many thanks to anyone who can throw any light on this.

[Clifford Pope]

An update on this.
It does this about once a month. The Lambda light comes on for the first time at start-up. It doesn't affect the running, he engine runs perfectly. I cancel the code, and it stays cancelled for weeks of daily use.
The concensus on Brickboard was that the code shouldn't exist for a Jetronic 2.4 system. So what, if anything, does it mean?

[Chris_Rogers]

If you have the correct title for the code it means that the fuel module is not getting the load signal from the ignition module, it needs this to determine fueling.
The most likely reason is a poor connection on one or both modules.
I would suggest you disconnect the battery, remove both modules and carefully clean the terminals. Also check the wirng between them.

[Clifford Pope]

Thanks Chris. The title comes from my Haynes, although it is not clear whether 1-4-4 is appropriate to the LH 2.4 or not.
Please can you tell me where to find the two modules you mention, and what they look like?
If one is getting a poor signal from the other, why does it make no difference to the running or fuel consumption? The engine just passed the MOT emissions check with flying colours.

[Chris_Rogers]

I'm afraid I have little information for your car, but similar systems were used in the early 850's I'm more familiar with.

From information I have the ignition module is fitted inside the car possibly in the passenger footwell maybe behind the cover on the door side. Not sure about the fuel module but maybe in the same location. Does Haynes give any clues? They are usually rectangular aluminium boxes about an inch think and about 4 by 5 inches. They will have a plug & socket on them with lots of wires comming out.

"If one is getting a poor signal from the other, why does it make no difference to the running or fuel consumption? The engine just passed the MOT emissions check with flying colours."

From what you say the problem is intermittent so may not show up other symptoms yet.

[Clifford Pope]

Thanks Chris, found them, looked at the connections, waggled them, they seem fine.
It's a curious and very infrequent occurence. The light has never come on while the engine is running - when it does, it just appears on the morning start-up, although perfect the night before. Cancelling it or not makes no difference, and it never re-appears if I do cancel it, until the process repeats a few weeks later.
Supposing the connections are fine, does that point to something beginning to go wrong inside a module, or can the diagnostic system itself develop a fault?

[Chris_Rogers]

>Thanks Chris, found them, looked at the connections, waggled
>them, they seem fine.
>It's a curious and very infrequent occurence. The light has
>never come on while the engine is running - when it does, it
>just appears on the morning start-up, although perfect the
>night before. Cancelling it or not makes no difference, and it
>never re-appears if I do cancel it, until the process repeats
>a few weeks later.

If the problem only occurs when cold starting it makes me suspect it's caused by low volts, maybe a loose connection somewhere or the ignition switch contacts.

>Supposing the connections are fine, does that point to
>something beginning to go wrong inside a module, or can the
>diagnostic system itself develop a fault?

The modules are very reliable I would doubt they are faulty I would have a look for poor fuse terminals, relay contacts or ignition switch contacts. Difficult with an intermittent fault, could be worth measuring battery volts on cranking maybe the battery is begining to fail.

[Clifford Pope]

Many thanks again Chris.