1997 Boxster OBC Hack

[Fulcrum]

Hello All,

I've just completed the OBC Hack using the instructions at www.pelicanparts.com, and I got nuthin'!!!!! There is no change in the display no matter which feature I try to access. I'll give the specifics below, if anybody has any ideas I would very much appreciate the assistance.

I have been told that since my center display (below the tach) already displays the temperature that my OBC is already enabled, so I didn't take it to the dealer. (COULD THIS BE THE PROBLEM? I have a Durametric, but not a PST2 or PIWIS - that is a different issue I'd like some help on some time. Do I need to take it to the dealer?).

I completed the instructions using two switches. The only deviation from the instructions that I did was to take the ground pins from each switch and tie them together to a single space connector to attach to the chassis ground.

I have confirmed all of my connections with an Ohm meter, both before re-assembly and after taking the cluster apart again when the project didn't work. I'm not an automotive professional, and while I'm not perfect, I have been able to earn a good living doing electrical/electronics engineering, assembly and repairs on some pretty cool stuff. I am certain the molex connectors are in the right slots, and the connections are good. The only thing I don't know is what happens to the molex connections after reassembly. One of the reasons I'm asking for help in this forum is I don't want to build a wiring harness extender to be able to run the car with the cluster on my work cart instead of installed in the dash ...;-(

The cluster worked completely normally after reassembly - except my OBC doesn't work ;-(

As I said, any thoughts, guidance, comments (and even sarcastic remarks) would be appreciated at this point.

:angry:

Fulcrum

[Tool Pants]

If you see the temp display then the OBC is on and nothing more needs to be done, and it should work if wired correctly.

How did you make the wiring harness? How are the switches wired? What numbered slots on the instrument cluster connector are you using?

[Fulcrum]

If you see the temp display then the OBC is on and nothing more needs to be done, and it should work if wired correctly.

How did you make the wiring harness? How are the switches wired? What numbered slots on the instrument cluster connector are you using?

Tool Pants: Thanks very much for the response.

I used the footwell light switch - installed and wired 2.

Working in the white instrument cluster connector (I have a 1997):

Slot 21 is wired to pin 1 on switch 1

Slot 25 is wired to pin 2 on switch 1

Slot 20 is wired to pin 1 on switch 2

Slot 22 is wired to pin 2 on switch 2

Pin 4 of both switches are wired to a single spade connector, which is connected to ground in the dash behind the instrument cluster.

The molex connectors are soldered onto the wire rather than crimped.

The female QDs on the switches are crimped on.

The spade connector for the ground wires is also crimped on.

Fulcrum

[Richard Hamilton]

The pin numbers you are using are correct. Just to be sure, did you make the connections to the WHITE cluster connector? On the switch there are 5 spade connections. The ground wire goes to the centre connection. The other two wires go to the terminals nearest the centre connection - not the ones nearer to the outside of the switch.

Other than that, I have no ideas.

[Fulcrum]

The pin numbers you are using are correct. Just to be sure, did you make the connections to the WHITE cluster connector? On the switch there are 5 spade connections. The ground wire goes to the centre connection. The other two wires go to the terminals nearest the centre connection - not the ones nearer to the outside of the switch.

Other than that, I have no ideas.

Nuts!!!

I am working in the white connector, and the switches are wired exactly as you say.

[Fulcrum]

The pin numbers you are using are correct. Just to be sure, did you make the connections to the WHITE cluster connector? On the switch there are 5 spade connections. The ground wire goes to the centre connection. The other two wires go to the terminals nearest the centre connection - not the ones nearer to the outside of the switch.

Other than that, I have no ideas.

Nuts!!!

I am working in the white connector, and the switches are wired exactly as you say.

Success!!!!

There were two problems. One was a bad switch - easy fix. The other was a ground problem - more difficult. I removed the instrument cluster and began checking continuity a third time, this time rather agressively wiggling the wires while doing the checks. I found the ground wire on the second switch to have a weak break. When the wire was stretched out and stationary with the instrument cluster removed, there was continuity, but when I wiggled the wire, the continuity was intermittent. I must have pinched the ground wire in some way while re-installing the cluster the first time. After replacing one switch, and re-doing the ground wire for the second switch, the hack works completely as advertised.

Thanks very much to those that responded. Chasing intermittent electrical faults can be extremely frustrating, but you gave me the confidence that I had done the hack correctly and led me to re-visit my workmanship.

Fulcrum