Super Select Flashing lights

Transmissions, transfer boxes, axles, drive shafts
Bo
Bomtek

Super Select Flashing lights

Mon Jun 22, 2009 2:24 pm

Many Pajero's (including Montero / Shogun variants ) owners at one time or another face is the dreaded 4x4 Super Select flashing light problem. It only takes a small amount of crud in the wrong place to upset the system so pays to acquaint yourself with it if you want to fix it yourself. (I understand that Super select is known as Active Trak in some models/countries).

NOTE: This article is based on a gen2.5 PETROL RHD vehicle, Also please note there are some differences between some models/engines - so your mileage may vary!

Flashing super select 4wd lights most often occur when the front differential automatic disconnect is not engaging /dis-engaging when you select/deselect 4x4 drive. Causes are:

- front differential sensor switch is damaged or faulty
- actuator rod/shaft jammed / seized (perhaps sand/mud/dirt)
- vacuum lines leak/popped off fittings
- vacuum solenoid valves (2no.) either maybe faulty
- electrical wiring connection issue (ecu/solenoids/switch)
- combination of the above

From the Montero / Pajero / Shogun forums it is clear that another common problem is flashing lights after repair work, for example after installing a new gearbox, or even a new radio.

Radio Installation
READERS TIP **** If you have just installed or replaced your radio/cassette/dvd player and you experience a new flashing light problem, check that you have not damaged or pulled a wire from the 4wd ecu (blue box) which is located just below the radio opening.

Other problems, for example the orange flashing light is also covered below.

How it works
It helps troubleshooting if you understand how the system should work. Pajero's have a four wheel drive system that allows the driver to engage 2 or 4wd, The rear differential is always driven, selecting 4wd engages the front differential free wheel, using a vacuum powered system.

The transfer gearbox (4wd) is mechanical (1998 GDI 3.5) so the selected gear is just that. Whatever the position of the transfer gearbox stick that is the gear you are in, it is a mechanical function.

The status of the system is indicated on the drivers console i.e. super select panel, however most often problems occur causing flashing lights, because there is a discrepancy between engaging/dis-engaging mechanism on the front differential and the transfer gearbox (t-case) gearstick position.

Lights
At ignition, in 2wd, the bottom pair of green lights are lite and stay lite constantly, because these lights are lite constantly, failure usually means a blown bulb(s).

The top pair of green lights flash briefly at startup but that is just an ECU start up check. If 4wd is properly selected and all the sensors are playing nicey, all four green lights are lite, and should not be flashing.

The main components of the system we need to look at are:

- super select light display
- Front differential
- Actuator
- Actuator shaft (and boot)
- Position sensor (the manual calls it the Free wheel engage switch)
- Vacuum control solenoid valves (x2)
- Vacuum piping (rubber and steel tubing)
- Vacuum tank (accumulator)
- 4WD ECU (electronic control unit)
- centre differential
- transfer gearbox

Troubleshooting
Most often the flashing light problem is an easy fix, primarily it happens because the 4wd system has not been regularly used. The 4wd must to be used regularly and exercised to keep it in good working order.

Assuming it's a Mk 1/2, the green lights are flashing because the system thinks that the front axle freewheel unit is still engaged and is trying to disengage it (or vice versa).

The system is operated via vacuum created by running engine (for petrol models) and is controlled by switches and electric solenoid valves. The solenoid valves on the bulkhead in front of the driver typically near the master cylinder. In turn they are connect to the actuator on the front axle by a mixture of steel and rubber piping. Once engaged (or disengaged) the position is verified by the free wheel sensor switch.

Fixing
This list should help you track down and the problem fault. Sometimes something simple, such as reversing a few metres helps dis-engagement with wheels straight helps too. If reversing doesnt solve the problem you probably have a problem that needs further investigation.

Basics
Check your fluids. Check the transfer box oil and front differential oil levels. Remove the top filler plug, both should be filled to the level of the bottom of the fill hole.

Any foul/burnt smell gritty texture indicates the oil is spent and an oil change is needed. Identify the correct oil from your manual. It is a good idea to change the fill and plug washers at the same time. On mine, when the diff gets hot oil leaks from the fill plug (another thing to add to my things to do list).

Tyres
Double check that all your tyres are the exactly same size and equal pressures. Slightly different tyre size / uneven wear may prevent correct engagement/dis-engagement.

Vacuum Solenoid Valves
A solenoid valve is a fancy term for an electrically controlled valve, in this case controlling vacuum to the Front differential actuator. On RHD drive models, the vacuum control solenoids are mounted near the top of the inner wheel tub, near the master cylinder. Vacuum is needed both to open, and close the actuator. Each typically identified with a blob of paint, yellow and blue. (see picture).
document_006.jpg
Electronic signals from the transfer box, to the gearbox ECU govern the operation of solenoids that control the vacuum feed to open and close the actuator located on the front differential.

The vacuum line with yellow strip, just visible in picture, connects to the solenoid with yellow paint blob, and in turn connects to front differential actuator. Same with the blue striped hose connecting to the solenoid with the blue blob of paint.

- Check that both solenoids are not sticking and operate correctly.
- Check the electrical resistance, should be approx. 39/45 ohms (Haynes states 45 ohms)
- Check the harness connection, apply electrical contact cleaner to clean connectors

Mounted on the cross member, near the front differential is a vacuum storage vessel, or acculumator. It is about the size of a tin of baked beans. worth checking for leaks, rust, lose connections, etc.

If you are greeted with flashing lights upon start up the vacuum accumulator (can) is unable to hold a vacuum, leaking or damage. Repair or replace. Also check that the vacuum line non-return valve is not leaking, causing accumulator to leak into the plenum overnight (refer to vacuum schematic drawing).

Vacuum Solenoids - top of wheel tub near master cylinder
Pajero 4wd Vacuum Solenoids



Actuator and shaft
Mount on the front differential, the actuator and shaft (covered with rubber boot) should be clean and free. Grease the actuator shaft under the rubber boot - they can seize and give a permanent flashing lights.

The actuator is circular shape, about 50mm in diameter.

Find someone you trust, lie under the car with the engine running while the "trusted" driver moves the transfer gear box (t-case) lever in and out of 4wd - you should see the shaft move.

If it is not moving is probably seized from lack of use, carefully pull back the rubber boot and get some grease on the actuator rod. Try and slide it - it should move fairly easily if you jack a wheel and turn it a bit.

If the shaft still doesn't move freely, pull each vacuum connection, and test if one, or other is sucking! (wise to ensure that the person behind the wheel knows what they are doing! - handbrake applied and auto in Park of course).

pajero 4wd flashing light fixing image

Key for images:
A - Actuator
B - Boot (covering actuator shaft)
C - Vacuum can (about the size of a tin of baked beans)
D - Differential (front)
E - Axle casing
F - Crossmember

Front Differential Actuator
Front Differential Actuator

Free Wheel Engage Switch
When change 2wd to 4wd and vice versa, the actuator moves the actuator shaft, and its position is monitored by the free wheel engage switch. If the actuator is moving and the shaft is free, then the next check is the free wheel engage switch. It either needs replacing or cleaning (bad connection). This is located above the actuator shaft and if you remove your bashplates can see it clearly.

To test continuity, whilst in 4wd, and igintion off, link across the connector. Upon restart if the flashing has stopped this confirms the wiring from the connector to the ecu is intact and the switch needs work (don't forget to remove the link and reinstate afterwards).

pajero flashing lights fix

Key for images:
A - Actuator
B - Boot (covering actuator shaft)
C - Vacuum can (about the size of a tin of baked beans)
D - Differential (front)
E - Axle casing
F - Crossmember

Vacuum Piping
The vacuum piping comprises a combination of steel tube and rubber hoses bascially routed from the engine through the solenoid valves to the actuator. The piping might be leaking, disconnected or perished. Also it is easy to miss reconnecting if you have just done other work in that area (been there done that!). The non-return valve may also be faulty.

You need to make sure that all the vacuum piping and hoses , and all connections are good. And don't forget without a hand vacuum pump the engine needs to be running to create the vacuum.

To help trace any leakage:

- Inspect the piping it might be damaged, leaking, spilt, cut, missing or perished.

- Temporary swap over the vacuum hoses (yellow and blue stripe outlet from solenoid valves) if lights stop flashing, the fault is either yellow stripe or blue stripe tubing. Replace hoses to orginal position and track pipe leakage. A hand vacuum pump is really handy since a vacuum leak can be difficult to identify.

- Test for continuity/blockage of piping. use a hand vaccum pump if available or alternately blow through disconnected pipe with helper underneath.

If you identify a leak or disconnected pipe just reconnecting may not be sufficient to solve the problem since dust and dirt will have been sucked into the soleniod valve.

Vacuum piping schematic diagram (pdf)

Click here for vaccum piping schematic diagram (PDF format 1 page)


Front axle (viewed from the front, beneath the radiator)
Pajero super select flashing light fix

Key for images:
A - Actuator
B - Boot (covering actuator shaft)
C - Vacuum can (about the size of a tin of baked beans)
D - Differential (front)
E - Axle casing
F - Crossmember


Automotive Hand Vacuum Pump
hand vacuum pump - helps to quickly identify leakage
Very useful tool to check vacuum piping.

Centre Differential - Orange flashing light
The transfer box (t-case) houses the centre differential, permitting drive to both front and rear wheels. On the super select panel it is represented as the central orange colour lamp, it is labelled "C/D Lock"

The manual I have indicates that there is a switch connector, from the centre diff, with a yellow/blue wire (which then changes to brown/black) and connects to the 4x4 ECU. If you have different year, or a rear diff locker the wiring is a bit more complex.

If you have the orange flashing light it is most probably an electrical issue with the centre differential detent switches on the transfer gear box (t/case), possibly a broken wire or fouled switch, could also be a poor connection due to mud/etc. There are five centre differential detent switches on the t/case for checking and inspection.


Vacuum Tank
If you lights flash furiously even before firing up your engine, it most likely a problem with the vacuum accumulator or the non-return valve (refer to piping). The acculumator is a small vacuum tank, to "store" or retain vacuum, it looks like a small tin can, about the size of a can of baked beans (the universal size guage) and it is located just behind the front differential with vaccum pipe connection.

Check the connection is secure, and tank itself is undamaged. Use hand vacuum pump if available to test for leakage.

On older models check for rust, if you are sure the tank is intact, perhaps add a coat of hammerite paint or equal. DONT paint or use any solvents until you are sure the can is sound, otherwise any weakness would allow contamination to be sucked into the vacuum system.


Transfer Gear box (t-case)
The wiring from the switches on the top of the transfer gearbox can perish/harden over time and have a tendency to break. Treat them with care! Check for wiring for clean connections, continuity and possible short circuit. Where possible clean connectors with electrical contact cleaner or equal.

transfer gearbox (t-case) sensor switches locations
Pajero flashing light fix - transfer case

Admin Edit: We acknowledge the original source of this -http://4wd.blogeasy.com/


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KaiV
Vehicle: Pajero
Location: Midrand, Gauteng
Posts: 648
Joined: Sat Jun 13, 2009 8:38 pm

Re: Super Select Flashing lights

Tue Sep 01, 2009 8:43 am

Hmmm interesting, though we now need advice on the Gen 4 and a laptop with an interface box to reset the ECU........

I am rather cheesed off at the moment with my Paj as in the middle of the desert i got the flashing light problem. It was the ctr difflock light that was flashing though, not the four green ones (which I beleive is typical of the Gen 2/3 models). We checked all connections under the car making sure they didn't get wet, checked all the vacum pipes and connections and really made sure that all was in good condition.

In my case a satalite call to the agents revealed to "please bring the vehicle to the nearest Mitsubishi dealer".................Grrrrr I was in the middle of the Namib desert :evil: . At the end though, we figured out that the Paj though in Limp mode, was in 4WD. Another satalite call to Spain to a Mitsubishi racing mechanic (all thanks to Kike who was with us on the desert trip) revealed that one could take power to the motor situated at the back of the transfer case which drives / changes the mode of the gearbox to "physically change" the position of the gearbox to another gearing (2H > 4H > 4Hcl or whatever the case) Luckily my Paj was in 4WD so we left it and managed the rest of the desert with no problems.

Once in Walvis, Volker at M + Z motors spent a couple of hours trying to figure out the problem. In my case the Laptop and interface box could not sort out / reset the problem. We tried putting power to the motor to get the vehicle (which was now in 4L???) back into 2H. The motor did not respond. Apparently the ECU locks it???
A lengthy investigation lead to the dropping of the gearbox to check the sensors on the top of the gearbox. One sensor cable was cleanly cut through. So, this was soldered together and put back. Unfortunatly I was only able to select 2H and 4H, and with selecting 4HCL, the flasing movie started all over again.

In my case there was a broken sensor cable. Impossible to detect without dropping the rear of the gearbox!!! How this came to break, heaven only knows. Paj is going in to be looked at and will report back.

This is the second time this has happened to me. The first time was after Atlantis dunes when the same thing happened, though locking the car and leaving it for a couple of minutes reset the problem...... only to re occur the next day at the first Bridgestone Fundi Challange in CT.... where the flashing light movie I got to watch cost an hour in recovering my Paj out of a dry river bed with it being stuch in 2H.......
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CATS
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Vehicle: 2001(Gen3) Pajero 3.2 Did, 2008(Gen4) Pajero Did
Location: Centurion
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Re: Super Select Flashing lights

Tue Sep 01, 2009 9:52 am

Eish!!!! :shock: Not good AT All!! When did it start flashing? While driving about normally or after you changed selection on the super select transfer case?

CATS
2009 Pajero 3.2 DiDc Lwb GLS (Gen4) - Casper (Starting to grow on me)
2001 Pajero 3.2 DiD Lwb GLS Manual (Gen3) - Snoopy (SOLD but not forgotten)
2008 Pajero 3.2 DiDc Lwb GLS Auto (Gen4) - Silvester (SOLD)
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KaiV
Vehicle: Pajero
Location: Midrand, Gauteng
Posts: 648
Joined: Sat Jun 13, 2009 8:38 pm

Re: Super Select Flashing lights

Wed Sep 02, 2009 2:01 pm

Paj in for two days.... Sensors being replaced :roll:
Last edited by KaiV on Thu Sep 03, 2009 12:16 pm, edited 1 time in total.
User avatar
KaiV
Vehicle: Pajero
Location: Midrand, Gauteng
Posts: 648
Joined: Sat Jun 13, 2009 8:38 pm

Re: Super Select Flashing lights

Thu Sep 03, 2009 7:40 am

Looks like a ECU or cabling problem now. All sensors have been replaced and gearbox is now responding :P :P :P
Last edited by KaiV on Thu Sep 03, 2009 12:18 pm, edited 1 time in total.
ro
robert

Re: Super Select Flashing lights

Thu Sep 03, 2009 8:59 am

Hi Bomtek.

What an explanation. For someone like me, not tecnical at all, it creates confusion understanding all the aspects an terminologies.
My question : I've got a Gen. 2 Pajero (LWB - 1994 - Petrol) and while engaged in 4WD the orange light is lit, but the top pair of green lights flash all the time. Does that mean that my (or the vehicle's :lol: ) 4WD is not properly working?

A further question : Your paragraph 3 refers to ".........occur when the front differential automatic disconnect is not engaging ....." etc. Can you enlighten me more on this statement. Please explain in more common language.

Many thanks.
Robert.
Gi
Gina

Re: Super Select Flashing lights

Thu Sep 03, 2009 6:47 pm

Wow, Kai, as another Gen 4 owner I was almost as worried as you :shock:
Hope the problem is sorted well and good now, but please keep us informed of any developments.
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KaiV
Vehicle: Pajero
Location: Midrand, Gauteng
Posts: 648
Joined: Sat Jun 13, 2009 8:38 pm

Re: Super Select Flashing lights

Mon Sep 07, 2009 8:17 am

All sorterd out :?

All the "switches" (actually sensors) have been replaced. It seems that the one switch cable which was cut (the biggest mystery) and joined (soldered) changed the resistance, hece the ECU being cunfuzled.

My biggest concern at the end of the day is:

*this should not have happened in the first place,
*how did the cable end up being cut???
*such little change in resistance should not lead to an ECU seeing this and stopping the operation of the gearbox!
*little or nothing one can do if this happens in the bush.

In the main article though, the basic idea if this does happen in the bush is to take a power lead from the battery to the actuator motor (which changes from 2H, 4H etc) and manualy change the setting. This is however easier said than done. In my case this said motors was not accepting a 12V feed (this we tried at the agents in Walvis), somehow the ECU is able to lock the actuator motor???

My worries are that both the agent in Namibia as well as my agent back home in JHB asked if I drove through water :? Well, my thoughts are so what..... its a 4x4, or does it seem that one can get 4x4's that arent allowed near water???
In the odd couple of water / river crossings I have done, I have never had a problem, though in sand (faaaar awaaaay form water) the sensors give me problems.

Well, as I said, she's sorted at the moment, lets see if it lasts :?
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Family_Dog
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Re: Super Select Flashing lights

Mon Sep 07, 2009 11:49 am

It seems that the one switch cable which was cut (the biggest mystery) and joined (soldered) changed the resistance,

My bold. This does certainly not sound right, unless it was resistance wire, which I very much doubt. Seems they had issues here before and probably cut the cable to insert a direct 12v connection (all surmised - I have no clue what the actual setup looks like here). But, with normal cable and a properly soldered joint, this cannot happen. My guess is that one of the switches was probably arcing and not making proper contact, leading to a resistive build up.

Whatever, good to know it's sorted!


-F_D
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ro
robin

Re: Super Select Flashing lights

Sat Dec 19, 2009 9:54 am

Any further developments on this matter. I am having a similar but intermittent problem, The latest time being in the sand in Southern Moz. The vehicle is a 2008 GLX with only 30 000km and has been checked by Mitsubishi in both Pretoria and Nelspruit. Similar type of responses ie diagnostics are fine and replaced snsor swithches

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