[Shotimes] Need help from the gurus again
George Fourchy
George Fourchy" <krazgeo@jps.net
Mon, 18 Nov 2002 23:21:24 -0800
On Mon, 18 Nov 2002 23:29:06 -0600, Rob Pittman wrote:
>What's a CCRM and a PCM and how can I tell if I'm having
>trouble getting power to them?
>
>Thanks once again for your help.
You're welcome!
The CCRM is the Constant Control Relay Module, or sometimes called the IRCM, or
Integrated Control Relay Module. It's located up on the radiator support, above the
radiator cooling fan, underneath the plastic cover panel that the smog sticker is
glued to. It supplies modulated power to multiple systems required for running the
engine, including the cooling fan and the fuel pump, and gets 12 volt DC power in
parallel with the PCM, or Powertrain Control Module, or more commonly, the engine
computer. It's located, in Tauri, in front of the glove compartment, with its nose
sticking thru the firewall, with the big 60 pin connector plugging into it right
under the right side hood lifter. The small power lead coming off the positive
battery terminal, that goes into a round, cylindrical connector a few inches down
the wire, then goes back toward the firewall on the passenger side is the power for
the computer (PCM) and the IRCM/CCRM. When that wire is unpowered or disconnected,
the CE light will be dimmer than normal, the fuel pump won't run when you turn the
key on, and the computer will be unpowered, and therefore store no codes, which is
why we couldn't figure out what was wrong with the Plus I have that was doing all
the teaching!! It was just by accident that a couple of friends and I, working on
two different cars at two different times, figured out that no power was the
problem. You will get spark to the plugs (if the crank sensor is good) with this
situation, since during start the computer apparently has little if anything to do
with spark generation and/or timing. We tested that while diagnosing the no-power
problem, and found strong spark at the plugs.
I have a wiring diagram that will tell me all the things the IRCM does, but it's
late, and there are others here who know more....the basic fact is that if it is
unpowered, it will kill the car.
The easiest way to tell you have no power is to see the dim CE light, and the backup
method is to not hear the fuel pump run for a second or two when you turn the key
on.
George