No start or power when key turned on

Hey friends I’m looking for some help diagnosing an issue with my neighbors truck, I am not super experienced when it comes to chasing electrical gremlins so bear with me. It is a 97 2.7l regular cab. He initially told me the truck was overheating occasionally and with no signs of a radiator leak and normal looking oil I popped the cap off the radiator and the antifreeze was disgusting. After draining and refilling with coolant system flush/distilled water I attempted to start it to let the cleaner work and truck wouldn’t start. He hadn’t driven it in awhile so I checked the battery and it had a 2/18 date so I replaced it for him. After battery replacement the truck still wouldn’t start and nothing powers on aside from the door chime. When you insert the key the chime turns on but if you try to do anything that takes electricity like blow the horn, turn signals they don’t work and the door chime turns off same result when you turn the key from accessory or first position to on. The truck does have an aftermarket security module setup and I can sometimes hear a relay clicking repeatedly after attempting to start the truck. I changed the starter relay, battery, and cleaned the main body ground but am unsure of where to go next. He’s an old man and I’d like to save him some money if I can help him out. Thanks in advance.

 

1st step is to recheck your terminal conditions and tightness.

 

sorry I didn’t add that in, terminals are clean and tight.

 

Next put a DVM on the battery and see the steady volts, then watch what happens when someone tries cranking it and let us know

 

10-4 I’ll have to recruit some help

 

12.4v steady even when turning the key to try and start.

 

The clicking sound is most likely the alarm control module relay for the alarm siren; it probably means the alarm is triggered but the siren is not connected. It is not necessary to remove the entire alarm system like most people would do, but if you disconnect the alarm's ground wire it should deactivate it. The location of that ground wire varies depending on the installation. If you locate the alarm "brain" box and disconnect the black wire from it, or even the whole large plug, that should do it.

Other than that, it sounds like maybe the battery cables at the battery are dirty, rotten or not connected well enough.

 

There's a 40amp AM2 fuse that needs to be checked under the hood

chime only sounds if key is in and on off and door opens...
as soon as you crank the key to anything but off.....chime will shut off

that tells you at least the main 80 amp fuse is good

 

I'd remove the alarm and return the wiring down there back to stock

 

thanks for the reply. I have found the alarm box. It is crudely wired in under the dash near the steering column and does look like it goes to a bank of 4-5 relays which is what clicks occasionally. There is a single black wire that I traced into the engine bay which goes to where I think maybe the distributor is? I will disconnect it and give it a shot.

 

thanks I’ll check out that fuse. Door chime is the only thing electrical that works currently.

 

going to give disconnecting it a shot

 

C’mon, baby!

 

Most of the time an aftermarket alarm is installed so that it only cuts off the starter or ignition when it is armed or triggered, so that's why you can just disconnect the alarm module and have normal operation.

This is also the reason why alarms have to be installed carefully so thehy are less vulnerable to being quickly disconnected.

Removai of the entire aftermarket alarm can be a big can of worms if you don't know how it was installed, or really take the time to carefully trace everything.

Plus if you just disconnect the main plug you haven't made any big changes that are may be tricky to reverse

 

What about the head lights...check those....should come on with or without a key

should get the buzzing warning if on, key off, and open the door


would not pull the alarm unless you take a bunch of pics and let everybody here eye em

I've seen three different......only one is plug and play......the others cut one of the ignition switch wires

 

This is why I lean towards a bad connection at the battery; its good enough for low amperage, but does not carry much load so it craps out when you draw more power

 

thats easy to test.....just jump from another vehicle
if everything powers up thats your problem

I doubt it tho.....no easy baskets

 

I haven’t removed anything. I did trace this single black wire from the viper module to the distributor plug. It is the purple wire that is spliced into one of the plug wires.

 

No headlights but when I twisted the knob to turn them on I got a series or relay clicks that happens after trying to start the truck as well.

 

Wow, some wiley installer put in an ignition cut. A risky move. I'm glad you found it, good work!