02 Ford Think: Service switch/fuse panel rewire (need pic or diagram)

Hello first time poster…

My 67yrld Dad with no tech skills bought a used 2002 Think. It runs fine but lights\wipers\brake lights don’t work. Someone told him the fuses next to the “Service switch” should be replaced. In process of pulling fuses the little fuse caps broke.

That’s where I come in, he asked me to help I do have 30yrs of automotive/electrical background in a hobby sense so I feel comfortable working most things, but have never even looked at a Ford Think in my life.

We decided to replace the switch fuse panel with a new toggle switch and three inline fuses. Before unplugging we pulled the whole panel away from the frame and in the process three wires broke off terminals, 1 from the Switch, 1 from the center big fuse and one from the bottom smaller fuse. I was able to identify the wire that goes to the service switch but took me an hour of trial and error to get the other two wires connected the correct way I believe but I am not positive.

After we were done the cart powers up and drives fine, but lights\wipers\brake lights still don’t work. In my mind that is fine I will just put in a power block and run new power to those things.

One weird side effect to the rewire is when I turn the service toggle off I get a plug indicator on the cluster that my dad says was never there.
Also the “parking brake light stays on, and I’ve definitely grounded the parking brake so not sure about that.

There were 3 orange wires that I was confused with, one I believe was a ground, one labeled dc/dc and one I think said mkt clstr.

I have looked for pics of the switch\fuse panel and wiring diagram but I can not locate what I am looking for any help would be much appreciated.

Thank you.

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I have the shop manual if you need it. Send email if so.

There are two dc to dc converters that go bad. They change the voltage from 72 volts to 12 volts. The first one is mounted on the passenger side on the frame under the front hood.in the area where a firewall would be on a normal car and the second is on the backside of the same frame which the entire front kick-up panel needs to be removed to gain access if you wanted to replace it. You can reach around and get to the wiring. They are both riveted on. They each have four wires going to them. The two input wires are a 72 volt positive wire and the next is 72 volt negative The two outputs are 12 positive and 12 volt negative. If you have 72 volts going in and not 12 volts coming out then the converter is bad. The one up front runs all your lights, horn, turn signal, wipers and several other things. If they are bad I would just upgrade the charger to a new delta q charger that has a built in dc to dc converter. It would require you to rewire somethings but it is cheaper and much better in the long run. Both converters are the same and you can interchange the wiring between the two as the wiring will reach. The last I seen the charger could be bought for $275 from evdrives. The old charger you can sell on ebay for around the same price as people will pay a premium for the factory charger as they don’t want to mess with wiring.

The charge indicator is a simple circuit. The charger sends a ground signal to the instrument cluster when the charger is not plugged in and takes the ground away when it is. I would start with checking the dc to dc converters and then check the grounds going to the instrument cluster and charger.

Same with the parking brake light. It’s just a ground wire. Usually the switch contacts at the parking brake handle just needs to be cleaned but could be a bad ground elsewhere.

Thank you very much for the reply and very helpful information.
If possible can you please also send me a pic of the wiring that connects to the back of the service switch panel below the seat and taken from the back seat so I can see the contacts?

If you can send me the service manual my email is deltreestar@gmail.com.


Manual sent.

The switch and fuses are pretty straight forward. All the info is in the shop manual. If you still need a picture I could take mine apart next week and take a picture for you.

Thank you very much for your help and the manual.

I too have the same issues of all the 12V accessories not working. I ordered a new dc dc converter and while waiting for it got stupid and started diagnosing to make sure I ordered the right part. I unplugged the converter (mine only has one on the back side of the cross rail or fore wall) and used a voltmeter to test the wires in the harness to make sure I had power going into the converter. I got a big spark out of one of them and when I tried to duplicate it, it never happened again, Before doing this, my lights, etc. would come on intermittently but after that, never again. After 10 days on order, my new converter arrived. I plugged it in to no avail. I fear I blew something while being impatient waiting for the converter. Anyone have any ideas where I should start looking? Thanks, Bob

Give me your email and I’ll send the manual. Sounds like you probably blew the fuse under the drivers seat.

My email is rldollar@aol.com
I pulled that fuse and went to every auto parts store in our area and everyone of them said that they can’t get it. One place checked it and said it was showing 10 which he said was good. Supposedly it is a 30 amp low current porcelain fuse. NAPA said they could get me one in a couple of days but I don’t know if it is really bad since it was tested and presumed good. The NEV store in the Phoenix area that I received the DC DC converter from said that they thought the power came through the instrument panel to the converter. I pulled the two harness connectors from there but didn’t go any further as I am a novice about these things. I would love a copy of the manual of you don’t mind. Thanks for your help. Bob

R.L. Dollar

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The orange wire with the yellow strip (OG/YE) at the dc/dc converter should have battery pack voltage (approximately 72 volts give or take a few volts) . The Orange and Black strip wire (OG/BK) at the dc/dc converter that is right beside the OG/YE wire is the 72 volt ground. So put your voltage meter on each of those wires to test for voltage. Make sure your meter is set to read dc voltage and the range is set above 80 volts. That wire is fused under the drivers seat. You should have 3 fuses under the seat and the dc/dc converter fuse should be the one that is furthest away from the disconnect switch or the top one depending on which model you have. Go to pages 40 and 41 of the electrical section of the service manual. Page 41 shows the dc/dc convertor. You then follow the OG/YE wire (E) up to page 40 and that page shows the fuse. The service disconnect switch needs to be on for it to supply power. The service disconnect switch is shown on page 39 which is fed directly from the battery pack.

I have also seen problems with the fuse holder itself so don’t overlook that as a possible problem. You could also switch the two outside fuses for testing. One is for the dc/dc converter and the other is for the charger.

If you follow the pinpoint tests in the manual don’t trust what it tells you to replace. I have found so many mistakes in the manual so ask before ordering parts.

Let us know if you need anymore help.

Dave, thank you so much for all your help and support. I’ve never joined a forum before but felt you had great knowledge on the think. Your advice made success on my rig. Everything now works thanks to you leading me in the right direction. It was a fuse under the seat. Thanks again, Bob

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Can I get a copy of that as well? Dthoms_8@yahoo.com

Sent, let me know if you don’t get it

Hi, I am having similar issues. I will try to sum up the issues and would appreciate any help.
I sent my charger back to delta Q when I got the error code of 6 red flashes at the bottom of the charger display. They sent it back and it all worked fine for about two weeks. I was getting charged and all was well. Then one day I got the 6 flashes again. Now the ford think cluster shows that it is plugged up and the car will not go at all.

I’ve run into this a couple times before. Both times were problems with the ground wire between the charger and battery pack. The first time my buddy had his batteries out and he forgot to put the charger ground wire back on. The ground wire is wrapped in orange tape at the batteries and needs to be hooked up to battery negative. The other time was the wire was broken where they did TSB 04-24-9 near the 4 pin charger connector on the harness side. The wire is black on the charger side and orange/black on the harness side. The problem was with the orange/black wire. You can ohm out the ground wire or a better test is to do a voltage drop on the ground wire. If it was me I would just remove the tape on the harness at the 4 pin charger connector and check were the TSB was done. Also check the wire at the connector itself. I’ve heard other people having problems in this area as well. If you need a copy of the service manual and TSB’s send me your email. Leaving on vacation early Thursday morning so if you need it let me know before then.

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Hello David…also looking for a service manual for the ford think. My email address is victorwyo@yahoo.com. Seeing the same symptoms as a bad ground wire some where. Ford Think has Plug In Icon showing, when not plugged and when plugged in and brake light icon also showing. Reading 72 volts at batteries but does not move. Thanks

Manual sent, let me know if you don’t get it.

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Can I get one too please. nelbo100@yahoo.com

Sent, let me know if you don’t get it.

Hello Dave,
Can you send me a copy of the manual? fjpabalan@aol.com

Thank you