E-Fan issue

[MichEnvoyGuy]

Years back (2018?), I installed the PCM of NC e-fan kit (3-relay) on my 08 Saab 97x 5.3i... its worked great until this year.

The issue I am having is, only 1 fan will turn on High speed when commanded - either the PCM or by the manual switch. I can swap the fan wiring harness back and forth, and the other fan will run high, so its not the fans themselves. Both low fans work on low speed as designed.

I have swapped the relays, no change. Still, only 1 fan kicks on high. Fuses are good. I do not know what else to check.

I wrote Kelly at PCM of NC and he suggested the wiring harness is bad, and for $125 + shipping I can be new again. But I thought I'd check first to see if anybody else has had this issue, or has any insight of how to troubleshoot this? I'd hate to spend the money to replace the wiring harness, and it not actually be the issue.

 

[mrrsm]

Sure...Try investigating THIS Dual E-Fan, Triple Relay Harness Deal (for around $40.00 with FREE S&H ) over on eBay ...instead:

Car Power Cooling Fan Wire Harness Kit Dual Electric Fan Upgrade Wiring Harness | eBay

1 Set of Harness. We will reply you within 24- 48 hours.

www.ebay.com

 

[Mooseman]

Break out the multimeter and trace each wire to be sure one isn't broken or melted. If possible, replace the affected wire. Save your $125.

 

[MichEnvoyGuy]

Sure...Try investigating THIS Dual E-Fan, Triple Relay Harness Deal (for around $40.00 with FREE S&H ) over on eBay ...instead:

Car Power Cooling Fan Wire Harness Kit Dual Electric Fan Upgrade Wiring Harness | eBay

1 Set of Harness. We will reply you within 24- 48 hours.

www.ebay.com

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No shit. Thanks for sharing that!! Would that be plug-n-play basically? The design of it (at least in the picture there) doesn't look any different than the PCM of NC kit.

 

[MichEnvoyGuy]

Break out the multimeter and trace each wire to be sure one isn't broken or melted. If possible, replace the affected wire. Save your $125.

Ok I am admittedly not good at all at electrical. I wouldn't even know where to start, or what to set the multimeter to. I'd probably blow something up. lol.

 

[Mooseman]

Most MM have a continuity testing mode with a tone when there is continuity or use any resistance mode and look for 0 resistance. I'm sure there's a YT video that can show how to do this. It's not that difficult.