cam and pulse sensors abnormal voltage

[cet]

No ignition on volvo 850.
unhooked harneses from pulse and cam sensors

pulse(crank) harness shows 1.8V on one lead(red/blk terminal A20 on Motronic 4.4) and milivolts on the other(Blu term. A6).

Camsensor has both the yel/red (A36) and blu/yel (A21) at about 11.7V.

I will admit to being nervous, but when a $300 part gives wrong voltages from 4 different terminals i worry.

I have seen in other posts that intermittancies in the ignition switch can cause abcense of 5v but the readings at the cam are above normal.

I can drag an occiliscope out of the attic and do dynamic testing of the sensors, but unless they have proper reference voltage from the computer i fail to see how this will help.

just to retest the secondary is it ok to ground out the blue terminal of the coil to check the coil function, resistances seemed OK

Thanx!

[Ozark Lee]

VADIS has a signal chart for every device on the car but unfortunately I don't have a working system with Windows XP at the moment and VADIS won't load under Linux. I am working on getting a dual boot system up right now and I will post a copy of the chart once I get it running unless someone else beats me to it.

I know that was helpful to you but I at least wanted to let you know that you aren't being ignored.

...Lee

[cet]

thank you lee, that will give me time to check to see if this is motronix4.4 any how, the only ignition detail is from Ebsco and may or may not be right (it shows a throttle position sensor that does not exist on the 96) thank you very much, i will drag the ocilliscope of the attic in anticipation.

[MadeInJapan]

My copy of VADIS shows the '96 no-turbo automatic to be either a MOTRONIC 4.3 or a FENIX system and lists up the values for FENiX but not for MOTRONIC...
Here is what it also says about voltage/signals for different sensors in the car (FENIX ONLY):

Signal descriptors.pdf

(23.16 KiB) Downloaded 597 times

[drsugg]

Well you made me do it. I've got the factory manual in front of me for 96 850 motronic 4.4. Voltage at cam sensor, Unplug sensor,check to engine ground to terminal #1, ground, 0 ohms, Terminal # 3 battery voltage, Terminal # 2 Battery voltage. Check terminal 1 with key off, terminal 2&3, key on. Turn key off and terminal 2 should show infinite resistance to engine ground. You are suppose to wait up to 245 seconds to check measurements after cycling the key. Speed sensor resistance is 200-500 ohms depending on temp. Terminal 2 on harness is 0 ohms with key off. terminal 1 to ground, 15-25 ohms with key off. Key on, voltage between terminals 1&2, 1-2 volts. They do not show any wave forms.

[cet]

Thank You all; drsugg, made in Japan, Ozark Lee, and stealth flow for helping out, i have learned a lot about the 850 thanks to you, with my previous experience being all 240. Your information caused me to go back in the other direction after finding the sensor voltages and resistances to all be good. In a 5 minute sequence, with my 14yr old cranking the engine i just put the multimeter to AC to see if the primary was throwing signal. Got about 0.18 millivolt at the crank sensor, about 0.52 millivolt at the input to the amplifier and about 5.5 Volts post amplifier.The coil seemed to have good resistance so i started putting things back together for the car to be towed to an auto electric shop. The next day something told me to try a different coil, found an external core coil from a 1992 Nissan Altima (had an old can coil from the 240 but figured that was too much of a stretch) rigged it in and the engine fired right up. This coil is slightly larger than the Bosch/Volvo but i think i can make it fit in the coil frame. Would there be any problem with running this until i can get up the bucks for the OEM?

[Ozark Lee]

Would there be any problem with running this until i can get up the bucks for the OEM?

If the primary coil resistance is about the same there shouldn't be any problem. The book spec on the primary resistance is 0.5 to 1.5 ohms.

...Lee