Overdrive on/off issue

[Profister]

Thanks Laura. I have no evidence to suspect that the transmission is malfunctioning yet; I just do not have experience driving a diesel truck and what I experience with the overdrive button looks odd to me. When I asked the dealer why this button did not make any difference he said that I was not driving fast enough for an overdrive mode and I bought his explanation (however I had some concerns). Later after driving my Delica on a highway I still did not see any difference and I opened this discussion to figure it out. While I am waiting for Bruce who is kindly looking for more detailed information about wiring etc. I am trying to collect as much information as possible about the way the transmission is supposed to behave and shifting points could narrow down the troubleshooting results.

Sergiy.

[Green1]

as per Marsgals description it appears I may have an adjustment to make then... because when I'm going up a hill and the engine is at 3000rpm, it will quite happilly and suddenly downshift to try to get more power... problem is, that puts the RPM up to 4500 which is something I don't like to have happen...

[marsgal42]

I find the overdrive behaviour is obvious even in city traffic.

Stop and disable the overdrive. Drive off, accelerate to 60 klicks or so. Note that the transmission only shifts up to third gear. Re-enable the overdrive and feel/hear the transmission shift in to 4th. Revs will drop from 2500 to 1800. You can hear the stereo again.

FWIW: when I drive up long hills like Gaglardi Way in Burnaby, or The Cut on Highway 1, I usually maintain 70 km/h at 3000 RPM in 3rd gear. The disabled overdrive is obvious coming down Gaglardi Way, with substantial engine braking at 60 to 70 km/h. You can't do this coming down The Cut at 110...

...laura

[Profister]

Thanks Laura. This info makes perfect sense to me. I will go for a test drive again tonight and post the results.

Sergiy.

[Profister]

Here are my test drive results. The upshifting points are 20, 40 and 60 km/h @2300-2500 rpm under normal conditions. Driving up The Cut on Hwy 1 at 80 km/h @3500 rpm seems normal. Overdrive on/off button does not make any difference under any circumstances. It is good to know now that the gear box works fine but the overdrive on/off button does not.

Sergiy.

[Mystery Machine]

Right - sorry it took so long to get back to you, but I have managed to track down the info that might be helpful to you?

Below are some images that show the location of the OD relay (inside the selector console) and also the OD wiring harness and solenoid at the gearbox end. I would check to see that the wiring has continuity from the switch to the relay and also from the relay to the wiring harness?





Check the connections at the gearbox end and worst case scenario, try and swap over the OD relay with another L300 owner to see if it might be the problem? If not, you might be looking at a solenoid problem?

Check the wiring first, then the relay, then the solenoid.

If you like, I can email you a full wiring diagram for the OD circuit (genuine mitsubishi diagram!)

Best of luck with it and let me know how you get on?

Bruce.

[Profister]

Wow! This is what I call troubleshooting! Now it rings another bell. I noticed a shuttering relay sound coming from the engine compartment twice already but I was thinking about the A/C relay as discussed in the 'Shuttering Relay' topic. The first time it happened during my very first trip when I was switching 4WD on and off driving in snow and the second time it happened with no reason at all. Now I think it is related to the overdrive control circuits.
Bruce, I will follow your directions and post the results. I might need to wait until the weekend though.
Thanks a million!

Sergiy.

[Profister]

This is the latest report on my troubleshooting following Bruce's recommendations. The picture shows that there was no relay found where it was supposed to be if the troubleshooting info was correct. Judging by the other technical posts on this forum I can imagine that the factory can change some details without documenting them for the public and the relay in my truck is located somewhere else. From the other hand the voltage on the solenoid connector goes on and off if the overdrive on/off button is pushed which leads to the conclusion that most likely I have to blame the solenoid for the 'overdrive off' malfunctioning. I have to find out what to do next I guess; well, I know what to do but I have to find a solenoid replacement to try.

[Profister]

Hello All,

Here is another happy ending story. Finally I found time to take care of the issue with overdrive 'off' as a part of a preparation to a trip to Northern BC. Yes, it was a defective solenoid as I expected after going through troubleshooting steps provided by Bruce aka Mystery Machine. Special thanks to Bruce for providing all the details for troubleshooting and Richard from RJD Services in North Vancouver who happened to be the only one I talked to being able to replace the solenoid on my request as a part of routine maintenance. Just to let everybody know that this issue was not the only one I found later that Silk Road Auto dealer considered not being a problem. Anyway I am a happy camper now and wish everyone happy ending to all Delica issues.

Sergiy.

[Mystery Machine]

Hi Sergiy,

I'm really glad to hear you got the OD sorted. I'm sorry about the wrong info on the relay....I was working on the new Mud Monkey the other day and I had the cover off the gear selector. I straight away noticed the lack of OD and starter relay and it really pissed me off that the info I have is wrong!

Despite the fact I had the cover off for something completely different, I was determined to find the relays....just so that I knew for future reference etc...

I found the starter relay - it's located under the service hatch behind the drivers seat, but I still can't track down the OD relay! I'll not give up looking though - I NEVER give up!

Anyway, glad you're fixed and running good. A happy ending.

Cheers for now,

Bruce.

[del-p25b]

I give Silk Road 1000% positive. I bought my p25 a few months ago and was worried about what service they may have done to it. I took it to a mechanic for a complete check up and the mechanic was very impressed with it indeed. The only problem I have had since then is a burned headlight which they replaced it for free and explained they have this type of issue with other buyers and are working to rectify it. I really cannot say enough about their honesty and service plus their committment to support you after the sale. Whoever here is not happy with Silk Road, I think that they should try calling Karim as he would for sure assist you and resolve the issue. Don't be shy.

By, the way my delica is a white p25.