Volvo AWD 850 Forum

INDEX FOR 10/2025(CURRENT) INDEX FOR 5/2016 850 INDEX

[<<]  [>>]


 VIEW    REPLY TO THIS MESSAGE Replies to this message will be emailed.    PRINT   SAVE 

Car cranks but won't run. No response on diagnostic ports A2 and A6 850 1994

posted by  benglar on  Sat Oct 3 18:36 CST 2009
Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
last visit: Mon Jul 5 09:23 CST 2010
[RELATED]

'94 Volvo 850 sedan, automatic transmission, not a turbo

The car cranks properly but the engine will not start. Dashboard lights appear normal while the starter motor turns.

While troubleshooting I discovered the engine coolant temperature sensor had failed and replaced it.

Here's the current problem: when using the diagnostic port, there is no LED response from A2 (MFI) and A6 (fuel) when I push the button for a second. Also no response when I hold the button for 6 seconds, the start of the process to clear the codes. The LED lights whenever the button is pressed but there is no answering LED activity from A2 and A6. The LED acts normally for other ports, including the transmission.

I have verified electrical continuity between A2/A6 and the B5 pin on the MFI and fuel computer boxes. I have verified that the main engine relay works.

Can someone please tell me which are the power pins on the fuel & engine computers so I can verify that they are getting power?

Any other troubleshooting ideas? At this point the Volvo diagnostic manual says I should try swapping in new engine and fuel computers. But gosh, I just don't have spares.

Thanks for the help.






THREADED THREADED EXPANDED FLAT PRINT ALL
MESSAGES IN THIS THREAD

New Car cranks but won't run. No response on diagnostic ports A2 and A6 [850][1994]
posted by  benglar  on Sat Oct 3 18:36 CST 2009 >


<< < > >>



©Jarrod Stenberg 1997-2022. All material except where indicated.


All participants agree to these terms.

Brickboard.com is not affiliated with nor sponsored by AB Volvo, Volvo Car Corporation, Volvo Cars of North America, Inc. or Ford Motor Company. Brickboard.com is a Volvo owner/enthusiast site, similar to a club, and does not intend to pose as an official Volvo site. The official Volvo site can be found here.