Dodge Caravan Hacking

If you’re really cool like me and own a decade old Dodge Grand Caravan you may find that the Totally Integrated Power Module (TIPM) will start failing.

In common cases (like mine) it will stop activating the fuel pump relay. This means your car will turn over but not start. This is not a great feature but does potentially help with the climate change crisis.

Fortunately for me I have a mechanic just down the street. I’d like to not tow this beast. To diagnose all of this the internet mechanics mention opening your TIPM and hot-wiring the fuel relay circuit. I took at the relay’s fuse and used a multimeter. No voltage. Spot checked some others and was reading the expected volts.

I shoved a jumper wire from my battery-wired cigarette port fuse (not the key activated one) over to the fuel pump relay fuse and heard what sounded like an electric motor activate from beneath the car.

I turned the ignition and the car started right up. Off to the mechanic.

Don’t Trust the Crazy Car Owner

I explained my morning’s adventures to the mechanic. He looked skeptically at my patch wire and said he’d run a test to diagnose things. Could be the TIPM, maybe just the fuel pump.

We both knew it was the TIPM. Turns out it was the TIPM. Shocker.

The fix: new TIPM. The problem: since these things fail so ofter and they’re year/make/model specific and there’s a worldwide computer chip shortage I get a refurbed one. Oh yeah, and it’s going to take a week to ship it.

Turns out no car for a week is fine. Thanks to COVID most necessities are all delivered now.

Bugs in the System

After some delays and fakeouts from TIPM dealers I got the call that the van was ready to go.

Walked up to the shop and it started right up. Settled the bill (ouch) and brought it home.

Next day the right turn indicator started flipping out “front right turn signal out”. Guess I get to make a stop at the auto supply joint. Looked up the bulb number but before making a purchase decided to physically check all the lights first. The front right fog light has been out for forever so I might as well fix that while I’m at it.

I activate the left turn signal: the left fog light starts flashing. What?

I activate the right turn signal: no lights flashing. Ok, expected.

I push the fog light button: bot turn signals turn on. What?

Quick call to the mechanic to describe the situation. Basically got the “wasn’t my fault” spiel which is fine, wasn’t casting blame just trying to problem-solve here.

There’s a lot of downtime at kid’s baseball games so between innings I start asking the internet what it thinks of all of this. Eventually I put in the correct series of search terms and land on someone having the same problem. I searched the document number in the images: “k6855837”.

It lands me on a YouTube video that take me step-by-step through the process of performing this fix.

Apparently my new-to-me TIPM has a firmware update that changed the behavior of some circuits. Just gotta flip some wires. Since it turned into a car maintenance day I took the opportunity to pick up some new H11 headlight sockets and wire them in since Dodge seems to use janky wiring that melts every few years.

And hooray, a car that starts with correctly functioning lights.

This is my last American car I swear.

Search terms:

TIPM

2011 Dodge Grand Caravan

Fog lights and turn signals switched

K6855837

fuel pump relay