Auto gearbox code 35 fault

[peter thomson]

Gearbox on my brothers VR4 has started to go into limp home mode and is showing code 35 (35 RED solenoid valve systematic short circuit/broken wire 23- 17).
Just turning of the ignition and restarting can clear the fault but it looks like it go's up the gears fine but when you go down a gear or come to a stop the box go's back in to limp home mode.
Is this a solenoid or cable fault? Any ideas guys

[Kieran]

Sounds like a sticky solenoid IMHO - If the wires were at fault I would expect the solenoid to be problematic on the upshift too - I think I'm right in saying that each solenoid controls both up and downshifting for each gear... Unless the 'signal' to change down is carried on a different wire to the solenoid.

[peter thomson]

Sounds like a sticky solenoid IMHO - If the wires were at fault I would expect the solenoid to be problematic on the upshift too - I think I'm right in saying that each solenoid controls both up and downshifting for each gear... Unless the 'signal' to change down is carried on a different wire to the solenoid.

If it's a solenoid do you think it just needs cleaned Kieran

Ran this morning for 3 miules without a problem but when left to go back home it went straight into limp home mode when it changed into 3rd I think. Also have a code 23 on the abs (23 Sol.RF-SHRT Right front solenoid Short circuit to +12 volt for the RF- solenoid ) Any chance this is related. ABS warning light does not come an while being driven

[Kieran]

Hmmm.... I'd be inclined to say 'Yes' you can often clean up a sticky solenoid - Or at least you can if it's something 'Dry' like a central locking one. However my knowledge/understanding of gearbox technology is not good and getting at the solenoid packs involves dropping the ATF and the sump - and then working out which of the solenoids (there's a pack of about 6 IIRC) is playing up.

Hmmmm. Having just read the Service manuals (both the Japanese one and the UK one), whilst the UK cars don't have the 'Red' solenoid, the diagnosis procedure appears identical.

What I would do is follow the procedure as outlined in the UK manual, and substitute the relevant bits from the Jap manual as required.

So - In the UK manual, start at 23-18. First thing to do is test the solenoids. This is mentioned in the UK manual on 23-54. The Japanese manual has the same details on page 23-58 and the jap manual shows the location of the RED solenoid (bottom left). The resistance values appear the same for both UK and Jap boxes (2.7~3.4ohm @ 20 degrees).

Both manuals then say to check wiring. The problem is whilst they mention the connectors to check, there's no diagram, so I'd guess the best thing is to check all the connectors on the gearbox at that point, then check the gearbox ECU connectors too.

Could be a bit of a sod to trace.... Thinking about it, you recently had that gearbox off to change the T/C seal didn't you? In that case I might start with the wiring first, it could've been damaged during that job maybe?

[peter thomson]

Just back from a run after checking the plugs and they all appear to be fine. This time it ran fine for 10 miles until I just got back and did the same thing again. Box would have been in 3rd and just putting power back on after a sharp 90 corner. Very intermittent. I was wrong with the abs codes, they are 22 and 23.
Not exactly sure what they mean.
I had a look at both manuals and it looks like we may well be checking the solenoids shortly.

[peter thomson]

All the solenoids as within spec and all are clicking but that may because the gearbox wasn't in limp home mode today when it was moved into the tent. Going to change them all anyway.
Also found that the blitz bov is completely seized.

[peter thomson]

No change gearbox went straight into limp home mode when car was restarted. Continuity of the wiring in the box was all checked and is fine. I'll swap in my ecu tomorrow to see if it makes any difference.
Sorted the BOV though but it needed the use of a vice to loosen off the piston. It had never been working going by the look of the chamber
Looks like it may be a new gearbox if we have no luck with the ecu.

[Nick Mann]

Is there any chance that one of the multiplugs is not connecting properly? There are two near the gear selector, to the left of the battery and down a bit, both of which have a fair few pins. I guess a bit of damp on just one of those could cause issues if the fit is not snug?

[peter thomson]

Hi Nick I had gone through all those the other week to no avail. I thought there was a chance of it being one of those as well after changing the TC seal in November. Workshop manual sems to imply trying the ecu next so trying that tomorrow.

Is there any chance that one of the multiplugs is not connecting properly? There are two near the gear selector, to the left of the battery and down a bit, both of which have a fair few pins. I guess a bit of damp on just one of those could cause issues if the fit is not snug?

[Nick Mann]

Okay. Good luck. I'm afraid I don't have any insight for you.

There is a bit in the workshop manual for the 4 speed V6 gearbox which shows how to take pressure readings from the gearbox to fault find. That may be worth a read.

Hopefully the ECU will solve the problem.

[peter thomson]

That's Ok had a read bat there isn't much info about on trying to repair them , well there will be when the manual eventually arrives.

Okay. Good luck. I'm afraid I don't have any insight for you.

There is a bit in the workshop manual for the 4 speed V6 gearbox which shows how to take pressure readings from the gearbox to fault find. That may be worth a read.

Hopefully the ECU will solve the problem.

[alex k]

hello, Do you switched the ecu? I think there is a broken wiring for this solenoid or it will fail when it gets hot.

[peter thomson]

hello, Do you switched the ecu? I think there is a broken wiring for this solenoid or it will fail when it gets hot.

Hi swapped ecu and changed the solenoids. I haven't been back to check the wiring yet

[alex k]

Does it work now? so, the solenoid was the failure?

[peter thomson]

Does it work now? so, the solenoid was the failure?

No solenoid replacement didn't work. That's why we are looking at the wiring next

[peter thomson]

As some of you may have read Keith's car was back with a code 35 with the gearbox after a coil pack failed and killed the engine ecu. Today we managed to replicate the fault while the car was stationary and the fault appears to be in the AT loom where it joins the engine loom. There is a nasty kink where the wires from the AT loom are joined to the engine loom. One of the wires here must have started to break up and cause an intermittent fault. I assume this is one of the 2 wires which power the 6 solenoids. At the moment the car is running fine again after removing the kink and at the moment I can no longer replicate the fault. The connection must have a better hold with the kink straigtened out.
Glenn has a loom on it's way so I'll be removing the loom from the gearbox to where it integrates with the engine loom near the bulkhead and hopefully all will be fine.
So the questiom is , is the other gearbox ok and was the fault always a wiring problem .We couldn't replicate this fault last time but as the fault code is the same there is a good chance the other box is fine.

[miller]

Phew its been a long haul Peter, hopefully thats it and its all sorted and Keith can finally enjoy the car.


Mike

[Nutter_John]

Good to see that you have found the fault Peter and hopefully it will fix the issue for sure .

[peter thomson]

Yes it certainly looks promising. I'm sure keith was pretty depressed this week but hopefully this is an end to the problem.
He needs to replace a front shock now as one of the Ralliart ones is leaking from the adjuster. I doubt there will be one on the go so he'll have to find something else to replace it with as they aren't cheap if you buy new ones

[Turbo_Steve]

It's a good job that car came with such a comprehensive warranty......oh no...sorry, I mean it's a good job Keith has such a jolly good friend and knowledgeable chap as yourself.