Hammer gurus- odd issue, please help
 

Hi All,

I just got a Bosch Hammer for my '90 C4. Everything works great- I can read all the installed modules/faults, direct drive all the drivable bits (fans, actuators, etc....) but I have one issue- the Hammer can not detect when the car is running. The upshot of this is that I can't get real-time output from the engine department sensors nor do an adaptation. To be clear- I can read the DME and activate the drivable bits (like the manifold tuning valve and the IAC valve) with no issue. Further, the car runs fine, maybe even great.

I have to assume that the RPM output is making it to the DME; again, the car runs fine and is entertainingly quick.

I also have to assume that the Hammer is working correctly. It will do everything I ask of it except the stuff that requires a running engine.

Consequently, I think the issue must be with the circuitry that communicates RPM to the diagnostic jack; either there's an issue with the output of the DME *or* an issue with the relay of same (have yet to check the wiring diagram; does the jack connect to the Central Informer?)

Also, having reviewed all the Rennlist and Pelican Hammer-related posts I find that I do not have the 19-pin official Porsche plug but rather a more-generic 4 pin plug to connect the Hammer to the car. I'm not sure that's an issue, however, as all the DIY products use a 4-pin connection too and they seem to be able to read live motor data.

Any input on where to start troubleshooting is greatly appreciated!

TIA,
Robert

is it chipped? sometmes that screws things up.

Dunno; not by my hand, but....

Pull out and open the DME to check, right?

I've done some further research and determined that my 4 prong interface cable may be the issue. John Speake of JDSPorsche fame answered an inquiry via email (immediately, I might add...) indicating that the Hammer needs to see a signal on the separate RPM signal line. He was also kind enough to tell me that the RPM pin (#14 on the car side) should be connected to Pin 1 on the Hammer end.

I'll mess about with it over the next few weeks and report back.

Another Hammer guru is Ingo, 3.6@cox.net

Not to hijack, but will the Hammer do the same for '84-'89 DME's?

Dunno; good question. Do you have a diagnostic plug? What's it look like?

Honestly, I dunno....

Never seen one and have always been under the impression it does not.

Well... the Hammer has to plug in somewhere; if it can't it can't Hammer, so if you don't have a diagnostic plug then no Hammer for you! (sorry ;) )