fjr diagnostic mode - please help!

[OAG]

So, with a Gen 2 (2006), when checking Diagnostic Code d:06, the number shown above the code is supposedly the ACTUAL collar temp? Mine is showing 108 at an ambient temp of 86. Think it might explain my radiator fans not starting up?

 

[mcatrophy]

So, with a Gen 2 (2006), when checking Diagnostic Code d:06, the number shown above the code is supposedly the ACTUAL collar temp? Mine is showing 108 at an ambient temp of 86. Think it might explain my radiator fans not starting up?

(collar -> coolant? Stupid spell checker?)
Don't know whether it would display in degrees (F or C?), or bananas.

Why not measure the sensor's resistance as per the workshop manual? (Page 8-231 or there abouts.) If you're considering changing it, you've got to dive in anyway.

 

[Fred W]

Well, it appears the readings on my first gen are at least close to being scaled in degrees Centigrade. My stone cold 1st gen shows Intake Temp (diAG:05) of 27 and Coolant Temp (diaAG:06) of 26. Ambient temp is ~70F (21C) but this doesn't seem consistent with other folks' second gen reports. These very well may just be arbitrary digital scales and different by generation.

 

[OAG]

Too bad It hasn't hacked up a code though, if it's like my Volvo this could be a nightmare! i guess I am going in!

 

[ionbeam]

The Gen II should be like the Gen I reading coolant temperature in ºC though there has been some Gen II confusion as Fred mentions. The Fault Code table reads verbatim between the two Gens service manuals.

The sensor is not a precision device, nor does it need to be. Ambient of 72º F should read ~22º C; 86ºF should read ~30ºC. If the Gen II really is in ºF a reading of 108º F with a real air temp of 86º F is probably close enough.

The kink is that no matter what the temperature sensor is reading, it is high for either ºC or ºF which should cause the fan to turn ON sooner and longer. The most common things that Gen II owners have been finding when the fans don't turn on at all or are intermittent have been bad relays, corroded pins in connectors and broken wires in the harness.

Since you are diAG savvy, go to diAG and try turning on the fans using the Actuation Function at diAG code 51 where toggling the red Run/Stop button on the handlebar will cause the radiator fan motor relay to turn on for 5 cycles of ON for 2 seconds/OFF 3 seconds and illuminates the engine trouble light. If the engine trouble light turns on but the fan doesn't you are troubleshooting a fan power problem and not a thermal switch problem.

 

[OAG]

Already ran the d:51, it worked properly. Checked fans with 12v battery direct, OK. I am not getting any fault codes, just working through it. Will start following wires today.

 

[ionbeam]

Already ran the d:51, it worked properly. Checked fans with 12v battery direct, OK. I am not getting any fault codes, just working through it. Will start following wires today.

I'll bite, how do you know that the fan isn't coming on when it should? Have you had an over-heat or have you seen all bars black on the temp gauge?

The results from your d:51 says that everything in your radiator fan circuit is working. If the ECU wanted to turn on the fans it could. If d:51 turned on the fans then the problem is the ECU doesn't think the fans should/need to turn on because of a temperature read error, or the problem is intermittent and the fans happened to work at the time you used d:51.

 

[OAG]

Nine bars on the temp gauge and the fans are still.

 

[ionbeam]

Nine bars on the temp gauge and the fans are still.

Hmm.

We know that the ECU is reading the temperature sensor because the Meter Assembly is displaying the temp on the bar graph.

We know that the ECU can control the fans because the fans worked when you used d:51.

We know that the power to the fans is present (in the driveway) because the fans worked when you used d:51.

The ECU monitors the temperature sensor and sends updates to the Meter Assembly to display the coolant temp, so the ECU is reading the sensor and processing the information. The ECU software has a set value that when exceeded will cause the ECU to send a ground via the Green/Yellow wire to the fan relay turning the relay ON and that sends power to the fans. All of this is shown to be working in the driveway. It makes it look like your problem may be intermittent and you happened to catch it working at your house.

Is there anything else that you didn't mention or forgot?

Was this a sudden onset problem where the fan never comes on or has it been intermittent?

 

[OAG]

This is going to sound bad, but I never hear the fans, I just noticed the temp was running high in a couple of stop and sit traffic jams. Upon further thought, I have noticed it during other hot days in the past, but haven't seen it indicated as this hot until this week. I commute on it but rarely get stuck in traffic. The gauge usually sits about dead center.

 

[ionbeam]

This is going to sound bad, but I never hear the fans...

Hey, this is just between you and me, nobody else needs to know. You get a major + sign for your ability and use of the diAG system to investigate your possible problem. Next time it's hot and you spend unusually long at a traffic light listen for the fans and see if there really is a problem and write back here and let us me know. "Never mind" would be the very best outcome

 

[OAG]

Fortunately, I can lean over and see if they are rotating! I said I was hard of hearing, NOT blind! Thanks for the thought, I appreciate good humor!